REMIND(1)                   General Commands Manual                  REMIND(1)



NAME
       remind - a sophisticated reminder service

SYNOPSIS
       remind [options] filename [date] [*rep] [time]

DESCRIPTION
       Remind  reads  the supplied filename and executes the commands found in
       it.  The commands  are  used  to  issue  reminders  and  alarms.   Each
       reminder  or alarm can consist of a message sent to standard output, or
       a program to be executed.

       If filename is specified as a single dash '-', then  Remind  takes  its
       input from standard input.  This also implicitly enables the -o option,
       described below.

       If filename happens to be a directory rather than a  plain  file,  then
       Remind  reads all of the files in that directory that match the pattern
       "*.rem".  The files are read in sorted order; the sort order may depend
       on  your  locale,  but should match the sort order used by the shell to
       expand "*.rem".

       Remind reads its files starting from the beginning to the end, or until
       it  encounters  a  line  whose  sole  content is "__EOF__" (without the
       quotes.)  Anything after the __EOF__ marker is completely ignored.


OPTIONS
       Remind has a slew of options.  If you're new  to  the  program,  ignore
       them for now and skip to the section "Reminder Files".

       -n     The -n option causes Remind to print the next occurrence of each
              reminder in a simple calendar format.  You can sort this by date
              by piping the output through sort(1).

       -j[n]  Runs  Remind  in  "purge"  mode to get rid of expired reminders.
              See the section PURGE MODE for details.

       -r     The -r option disables RUN directives and the shell()  function.
              As of Remind 3.00.17, using -u implies -r.

       -c[flags]n
              The  -c  option causes Remind to produce a calendar that is sent
              to standard output.  If you supply a number n, then  a  calendar
              will be generated for n months, starting with the current month.
              By default, a calendar for only the current month is produced.

              You can precede n (if any) with a set of flags.  The  flags  are
              as follows:

              '+'    causes a calendar for n weeks to be produced.

              'a'    causes Remind to display reminders on the calendar on the
                     day they actually occur as well as on any preceding  days
                     specified by the reminder's delta.

              'l'    causes  Remind  to  use  VT100 line-drawing characters to
                     draw the calendar.  The  characters  are  hard-coded  and
                     will  only  work on terminals that emulate the VT00 line-
                     drawing character set.

              'u'    is similar to 'l', but causes Remind to use UNICODE line-
                     drawing  characters to draw the calendar.  The characters
                     are hard-coded and will only work on terminals  that  are
                     set to UTF-8 character encoding.

              'c'    causes  Remind  to use VT100 escape sequences to approxi-
                     mate SPECIAL COLOR reminders.  Note  that  this  flag  is
                     kept  for  backwards-compatibility;  you  should  use the
                     -@[n][,m] command-line option instead.


       -@[n][,m]
              Tells Remind to approximate SPECIAL COLOR reminders using  VT100
              escape  sequences.   The  approximation  is  (of necessity) very
              coarse,  because  the  VT100  only  has  eight  different  color
              sequences, each with one of two brightnesses.  A color component
              greater than 64 is considered "on", and  if  any  of  the  three
              color  components  is  greater than 128, the color is considered
              "bright".

              If you supply the optional numeric parameters, the have the fol-
              lowing  meanings:  n=0 tells Remind to use the standard 16 VT100
              colors.  n=1 tells it to use an extended 256-color palette  sup-
              ported  by many terminal emulators such as xterm.  And n=2 tells
              it to use escape sequences  that  support  true  24-bit  colors,
              again supported by many terminal emulators such as xterm.

              If  the optional m parameter is supplied following a comma, then
              m=0 tells Remind that  the  terminal  background  is  dark,  and
              Remind  will  brighten  up dark colors to make them visible.  If
              m=1, then Remind assumes the terminal background is light and it
              will darken bright colors to make them visible.  If no m is sup-
              plied, then Remind does not perform any  adjustments,  and  some
              reminders  may  be hard or impossible to see if the color is too
              close to the terminal background color.

       -wcol[,pad[,spc]]]
              The -w option specifies the output width, padding and spacing of
              the formatted calendar output.  Col specifies the number of col-
              umns in the output device.  If not specified, or specified as 0,
              it defaults to the larger of 71 or the actual width of your ter-
              minal, or to 80 if standard output is not a terminal.

              Pad specifies how many lines to  use  to  "pad"  empty  calendar
              boxes.   This defaults to 5.  If you have many reminders on cer-
              tain days that make your calendar too large to fit  on  a  page,
              you  can  try reducing pad to make the empty boxes smaller.  Spc
              specifies how many blank lines to leave between the  day  number
              and the first reminder entry.  It defaults to 1.

              Any of col, pad or spc can be omitted, providing you provide the
              correct number of commas.  Don't use any spaces in the option.

       -s[a]n The -s option is very similar to the -c option, except that  the
              output  calendar  is  not  formatted.  It is listed in a "simple
              format" that can be used as input for more sophisticated  calen-
              dar-drawing  programs.   If n starts with "+", then it is inter-
              preted as a number of weeks.

              If you immediately follow the s with the letter a,  then  Remind
              displays  reminders  on  the  calendar  on the day they actually
              occur as  well  as  on  any  preceding  days  specified  by  the
              reminder's delta.

       -p[a][p][p]n
              The  -p option is very similar to the -s option, except that the
              output contains additional information for  use  by  the  Rem2PS
              program,  which creates a PostScript calendar, and various other
              back-end programs.  For this option, n cannot start with "+"; it
              must specify a number of months.  The format of the -p output is
              described in the rem2ps(1) man page.  If you immediately  follow
              the  p  with the letter a, then Remind displays reminders on the
              calendar on the day they actually occur as well as on  any  pre-
              ceding  days  specified  by the reminder's delta.  If you follow
              the p with another p, then  Remind  uses  a  more  comprehensive
              JSON-based  format  rather  than  the  "simple calendar" format.
              This format is  also  documented  in  the  rem2ps(1)  man  page.
              Finally,  if  you  use three p's, as in -ppp, then Remind uses a
              pure JSON format, again documented in rem2ps(1).

              Note that the -pp or -ppp options also enable the -l option.

       -l     If you use the -l option in conjunction with the -p option, then
              Remind outputs additional information for back-end programs such
              as rem2ps.  This additional information lets the  back-end  pro-
              grams  correlate a reminder with the source file and line number
              that produced it.

       -m     The -m option causes the -c or -p options to produce a  calendar
              whose first column is Monday rather than Sunday.  (This conforms
              to the international standard.)

       -v     The -v option makes the output of Remind slightly more  verbose.
              Currently,  this  causes Remind to echo a bad line in case of an
              error, and to print a security message if  a  script  tests  the
              $RunOff system variable.

       -o     The -o option causes Remind to ignore all ONCE directives.

       -t     The   -t   option  causes  Remind  to  trigger  all  non-expired
              reminders, regardless of the delta supplied for each reminder.

       -tn    If you supply a number n after the -t option, then  Remind  pre-
              tends  that  each non-expired reminder has a delta of n days and
              triggers reminders accordingly.

       -h     The -h option ("hush...") suppresses certain warning and  infor-
              mation  messages.  In particular, if no reminders are triggered,
              this mode produces no output.

       -a     The -a option causes Remind not  to  immediately  trigger  timed
              reminders  that  trigger  on  the  current  day.  It also causes
              Remind not to place timed reminders in a calendar.  If you  sup-
              ply  two  or  more  -a  options,  then Remind will trigger timed
              reminders that are in the future, but  will  not  trigger  timed
              reminders  whose  time  has  passed.  (Regardless of how many -a
              options you supply, Remind will not include timed  reminders  in
              the calendar if at least one -a option is used.)


       -q     The  -q  option  causes  Remind not to queue timed reminders for
              later execution.

       -f     The -f option causes Remind to remain  in  the  foreground  when
              processing  queued  reminders,  rather  than forking off a back-
              ground process to handle them.

       -e     The -e option diverts error messages (normally sent to the stan-
              dard error stream) to the standard output stream.

       -dchars
              The  -d option enables certain debugging modes.  The chars spec-
              ify which modes to enable:

         e      Echo all input lines

         x      Trace all expression evaluation

         t      Display all trigger date computation

         v      Dump the variable table after execution of the reminder script

         l      Echo lines when displaying error messages

         f      Trace the reading of reminder files

       -g[a|d[a|d[a|d[a|d]]]]
              Normally, reminders are issued in the order in  which  they  are
              encountered  in the reminder script.  The -g option cause Remind
              to sort reminders by date and time prior to issuing  them.   The
              optional a and d characters specify the sort order (ascending or
              descending) for the date, time and  priority  fields.   See  the
              section "Sorting Reminders" for more information.


       -b[n]  Set  the  time  format for the calendar and simple-calendar out-
              puts.  N can range from 0 to 2, with the default 0.  A value  of
              0  causes  times  to  be  inserted in 12-hour (am/pm) format.  1
              causes times to be inserted in 24-hour format,  and  2  inhibits
              the automatic insertion of times in the calendar output.

       -x[n]  Sets  the  iteration  limit for the SATISFY clause of a REM com-
              mand.  Defaults to 150.

       -kcmd  Instead of simply printing MSG-type reminders, this causes  them
              to  be  passed to the specific cmd.  You must use '%s' where you
              want the body to appear, and may need to enclose this option  in
              quotes.   Note  that  all  shell  characters  in the body of the
              reminder are escaped with a backslash, and the  entire  body  of
              the  reminder  is  passed  as a single argument.  Note that this
              option overrides the -r option and the RUN OFF command.

              As an example, suppose you have an X Window program called xmes-
              sage  that  pops  up  a window and displays its invocation argu-
              ments.  You could use:

                        remind '-kxmessage %s &' ...

              to have all of your MSG-type reminders processed using xmessage.

              A word of warning: It is very easy to spawn dozens  of  xmessage
              processes  with  the  above  technique.   So  be  very  careful.
              Because all shell and whitespace  characters  are  escaped,  the
              program  you execute with the -k option must be prepared to han-
              dle the entire message as a single argument.

       -z[n] Runs Remind in the daemon mode.  If n
              is supplied, it specifies how often (in minutes)  Remind  should
              wake  up  to  check  if the reminder script has been changed.  N
              defaults to 1, and can range from 1 to 60.  Note that the use of
              the -z option also enables the -f option.

              If  you  supply  the  option  -z0, Remind runs in a special mode
              called server mode.  This is  documented  in  the  tkremind  man
              page; see tkremind(1).

       -uname Runs  Remind with the uid and gid of the user specified by name.
              The option changes the uid and gid as described,  and  sets  the
              environment  variables  HOME,  SHELL and USER to the home direc-
              tory, shell, and user name, respectively, of the specified user.
              LOGNAME  is also set to the specified user name.  This option is
              meant for use in shell scripts that mail reminders to all users.
              Note  that  as of Remind 3.00.17, using -u implies -r -- the RUN
              directive and shell() functions are disabled.

              Non-root users can also use the -u  option.   However,  in  this
              case,  it  only  changes  the environment variables as described
              above.  It does not change the effective uid or gid.

       -y     Causes Remind to synthesize a tag for any reminder that lacks  a
              TAG clause.

       -ivar=expr
              Sets  the value of the specified var to expr, and preserves var.
              Expr can be any valid Remind expression.  See the section  "Ini-
              tializing Variables on the Command Line" for more details.

       -ifunc(args)=definition
              Allows you to define a function on the command line.

       If  you supply a date on the command line, it must consist of day month
       year, where day is the day of the month, month is at  least  the  first
       three letters of the English name of the month, and year is a year (all
       4 digits) from 1990 to about 2075.  You can leave out  the  day,  which
       then defaults to 1.

       If  you  do  supply  a  date  on the command line, then Remind uses it,
       rather than the actual system date, as its  notion  of  "today."   This
       lets  you  create  calendars for future months, or test to see how your
       reminders will be triggered in the future.  Similarly, you can supply a
       time to set Remind's notion of "now" to a particular time.  Supplying a
       time on the command line also implicitly enables the -q option and dis-
       ables  the -z option.  The time may be specified in 24-hour format (eg,
       13:20) or common "AM/PM" format (1:20pm).

       If you would rather specify the date more succinctly, you can supply it
       as  YYYY-MM-DD  or  YYYY/MM/DD.  You can even supply a date and time on
       the command line as one argument: YYYY-MM-DD@HH:MM.

       In addition, you can supply a repeat  parameter,  which  has  the  form
       *num.  This causes Remind to be run num times, with the date increment-
       ing on each iteration.  You may have to enclose the parameter in quotes
       to  avoid  shell expansion.  See the subsection "Repeated Execution" in
       the section "Calendar Mode" for more information.

REMINDER FILES
       Remind uses scripts to control its operation.  You  can  use  any  text
       editor capable of creating plain ASCII files to create a Remind script.
       The commands inside a script can range from the very simple and  almost
       immediately understandable:

            REM 6 Jan MSG Dianne's birthday

       to the baroque and obscure:

            REM [date(thisyear, 1, 1) + 180] ++5 OMIT \
            sat sun BEFORE MSG [ord(thisyear-1980)] payment due %b!

       A  reminder file consists of commands, with one command per line.  Sev-
       eral lines can be continued using the backslash character,  as  in  the
       above example.  In this case, all of the concatenated lines are treated
       as a single line by Remind.  Note  that  if  an  error  occurs,  Remind
       reports the line number of the last line of a continued line.

       Remind  ignores  blank  lines,  and lines beginning with the '#' or ';'
       characters.  You can use the semicolon as a comment  character  if  you
       wish  to pass a Remind script through the C pre-processor, which inter-
       prets the '#' character as the start of a pre-processing directive.

       Note that Remind processes line  continuations  before  anything  else.
       For example:

            # This is a comment \
            This line is part of the comment because of line continuation \
            and so on.
            REM MSG This line is not ignored (no \ above)

       Remind  is  not  case  sensitive;  you can generally use any mixture of
       upper- or lower-case for commands, parameters, invocation options, etc.

THE REM COMMAND
       The most powerful command in a Remind script is the REM command.   This
       command is responsible for issuing reminders.  Its syntax is:

              REM  [ONCE]  [date_spec] [back] [delta] [repeat] [PRIORITY prio]
              [SKIP | BEFORE | AFTER] [OMIT  omit_list]  [OMITFUNC  omit_func-
              tion]  [AT time [tdelta] [trepeat]] [SCHED sched_function] [WARN
              warn_function] [UNTIL expiry_date | THROUGH last_date] [SCANFROM
              scan_date  | FROM start_date] [DURATION duration] [TAG tag] <MSG
              | MSF | RUN | CAL | SATISFY | SPECIAL special  |  PS  |  PSFILE>
              body

       The parts of the REM command can be specified in any order, except that
       the body must come immediately after the MSG, RUN, CAL, PS,  PSFILE  or
       SATISFY keyword.

       The  REM token is optional, providing that the remainder of the command
       cannot be mistaken for another Remind command such as OMIT or RUN.  The
       portion  of  the  REM  command  before the MSG, MSF RUN, CAL or SATISFY
       clause is called a trigger.

       MSG, MSF, RUN, CAL, SPECIAL, PS and PSFILE

       These keywords denote the type of the reminder.  (SATISFY is more  com-
       plicated  and  will  be explained later.)  A MSG-type reminder normally
       prints a message to the standard output, after passing the body through
       a  special substitution filter, described in the section "The Substitu-
       tion Filter."  However, if you have used the  -k  command-line  option,
       then  MSG-type  reminders  are passed to the appropriate program.  Note
       that the options -c, -s, -p and -n disable the -k option.

       Note that you can omit the reminder type, in which case it defaults  to
       MSG.  So you can write:

            6 January Dianne's Birthday

       although this is not recommended.

       The  MSF keyword is almost the same as the MSG keyword, except that the
       reminder is formatted to fit into a paragraph-like format.  Three  sys-
       tem  variables  control the formatting of MSF-type reminders - they are
       $FirstIndent, $SubsIndent and $FormWidth.  They are  discussed  in  the
       section "System Variables."  The MSF keyword causes the spacing of your
       reminder to be altered - extra spaces are discarded, and two spaces are
       placed  after  periods and other characters, as specified by the system
       variables $EndSent and $EndSentIg.   Note  that  if  the  body  of  the
       reminder   includes  newline  characters  (placed  there  with  the  %_
       sequence), then the newlines are treated as the beginnings of new para-
       graphs,  and  the  $FirstIndent  indentation is used for the next line.
       You can use two consecutive newlines to have spaced paragraphs  emitted
       from a single reminder body.

       A  RUN-type reminder also passes the body through the substitution fil-
       ter, but then executes the result as  a  system  command.   A  CAL-type
       reminder  is  used  only to place entries in the calendar produced when
       Remind is run with the -c, -s or -p options.

       A PS or PSFILE-type reminder is used to pass PostScript  code  directly
       to  the  printer when producing PostScript calendars.  This can be used
       to shade certain calendar entries (see the psshade() function), include
       graphics in the calendar, or almost any other purpose you can think of.
       You should not use these types of reminders unless you  are  an  expert
       PostScript  programmer.  The PS and PSFILE reminders are ignored unless
       Remind is run with the -p option.  See the section  "More  about  Post-
       Script" for more details.

       A  SPECIAL-type reminder is used to pass "out-of-band" information from
       Remind to a calendar-producing back-end.  It should be  followed  by  a
       word  indicating  the type of special data being passed.  The type of a
       special reminder depends on the back-end.   For  the  Rem2PS  back-end,
       SPECIAL  PostScript  is  equivalent  to a PS-type reminder, and SPECIAL
       PSFile is equivalent to a PSFILE-type reminder.  The body of a  SPECIAL
       reminder  is  obviously  dependent  upon the back-end.  A back-end must
       ignore a SPECIAL that it does not recognize.

       DATE SPECIFICATIONS

       A date_spec consists of zero to four parts.  These parts are  day  (day
       of month), month (month name), year and weekday.  Month and weekday are
       the English names of months and weekdays.  At  least  the  first  three
       characters  must  be  used.   The following are examples of the various
       parts of a date_spec:

       day:   1, 22, 31, 14, 3

       month: JANUARY, feb, March, ApR, may, Aug

       year:  1990, 1993, 2030.  The year can range from 1990 to 2075.

       weekday:
              Monday, tue, Wed, THU, Friday, saturday, sundAy

       Note that there can be several weekday components separated  by  spaces
       in a date_spec.

       INTERPRETATION OF DATE SPECIFICATIONS

       The following examples show how date specifications are interpreted.

       1.  Null date specification - the reminder is triggered every day.  The
       trigger date for a specific run is simply the current system date.

       2. Only day present.  The reminder is triggered on the specified day of
       each  month.  The trigger date for a particular run is the closest such
       day to the current system date.  For example:
            REM 1 MSG First of every month.
            REM 31 MSG 31st of every month that has 31 days.

       3. Only month present.  The reminder is  triggered  every  day  of  the
       specified month.  Example:
            REM Feb MSG Every day in February

       4.  day and month present.  Examples:
            REM 6 Jan MSG Every 6th of January
            REM Feb 29 MSG Every 29th of February

       5.  Only year present. Example:
            REM 1991 MSG Every day in 1991

       6.  year and day present.  Examples:
            REM 1 1990 MSG 1st of every month in 1990
            REM 1992 23 MSG 23rd of every month in 1992

       7.  year and month present.  Examples:
            REM Feb 1991 MSG Every day in Feb 1991
            REM 1992 September MSG Every day in Sept 1992

       8.  year, month and day present.  Examples:
            REM 8 Jan 1991 MSG 8th January 1991.
            REM 1992 March 9 MSG 9th March 1992.

       9.  weekday only.  Examples:
            REM Sat MSG Every Saturday
            REM Mon Tue Wed Thu Fri MSG Every working day
            REM Monday Wednesday MSG Every Monday and Wednesday

       10.  weekday and day present.  Examples:
            REM Sat 1 MSG First Saturday of every month
            REM Mon Tue Wed Thu Fri 15 \
                 MSG 1st working day after 15th of every month

       11.  weekday and month present.  Examples:
            REM Mon March MSG Every Monday in March
            REM Mon Tue Wed Thu Fri Feb MSG Every working day in February

       12.  weekday, month and day present.  Examples:
            REM Mon 1 March MSG First Monday in March
            REM Sat Sun 15 July MSG First Sat or Sun on or after 15 July

       13.  weekday and year present.  Example:
            REM Sat Sun 1991 MSG Every Saturday and Sunday in 1991

       14.  weekday, day and year present.  Examples:
            REM Mon 15 1990 MSG 1st Mon after 15th of every month in 1990
            REM Mon Tue Wed Thu Fri 1 1990 \
                 MSG 1st working day of every month in 1990

       15.  weekday, month and year present.  Example:
            REM Mon Wed 1991 Feb MSG Every Mon and Wed in Feb 1991.

       16.  weekday, day, month and year present.  Example:
            REM Mon Tue Wed Thu Fri 28 Oct 1990 \
                 MSG 1st working day on or after 28 October 1990.

       Note  that  when both weekday and day are specified, Remind chooses the
       first date on or after the specified day that also satisfies the  week-
       day constraint.  It does this by picking the first date on or after the
       specified day that is listed in the list of weekdays.  Thus, a reminder
       like:

            REM Mon Tue 28 Oct 1990 MSG Hi

       would  be  issued  only  on  Monday, 29 October, 1990.  It would not be
       issued on Tuesday, 30 October, 1990, since the 29th is the  first  date
       to satisfy the weekday constraints.

       SHORT-HAND DATE SPECIFICATIONS

       In addition to spelling out the day, month and year separately, you can
       specify YYYY-MM-DD or YYYY/MM/DD.  For example,  the  following  state-
       ments are equivalent:

            REM 5 June 2010 MSG Cool!
            REM 2010-06-05  MSG Cool!

       You can also specify a date and time as YYYY-MM-DD@HH:MM.  These state-
       ments are equivalent:

            REM 19 Dec 2010 AT 16:45 MSG Hi
            REM 2010-12-19@16:45 MSG Hi

       There's one subtlety with short-hand date specifications:  The  follow-
       ing statements are not equivalent:

            REM 19 Dec 2010 AT 16:45 +60 MSG Hi
            REM 2010-12-19@16:45 +60 MSG Hi

       In  the second statement, the "+60" is a delta that applies to the date
       rather than a tdelta that applies to the time.  We recommend explicitly
       using the AT keyword with timed reminders.

       THE REMIND ALGORITHM

       Remind uses the following algorithm to compute a trigger date: Starting
       from the current date, it examines each day, one at a  time,  until  it
       finds a date that satisfies the date specification, or proves to itself
       that no such date exists.  (Actually, Remind merely behaves  as  if  it
       used  this  algorithm;  it  would be much too slow in practice.  Inter-
       nally, Remind uses much faster techniques to calculate a trigger date.)
       See DETAILS ABOUT TRIGGER COMPUTATION for more information.

       BACKWARD SCANNING

       Sometimes,  it  is necessary to specify a date as being a set amount of
       time before another date.  For example, the  last  Monday  in  a  given
       month  is computed as the first Monday in the next month, minus 7 days.
       The back specification in the reminder is used in this case:

            REM Mon 1 -7 MSG Last Monday of every month.

       A back is specified with one or two  dashes  followed  by  an  integer.
       This  causes Remind to move "backwards" from what would normally be the
       trigger date.  The difference between --7 and -7 will be explained when
       the OMIT keyword is described.

       ADVANCE WARNING

       For some reminders, it is appropriate to receive advance warning of the
       event.  For example, you may wish to be reminded of someone's  birthday
       several days in advance.  The delta portion of the REM command achieves
       this.  It is specified as one or two "+" signs followed by a number  n.
       Again,  the difference between the "+" and "++" forms will be explained
       under the OMIT keyword.  Remind will trigger the reminder  on  computed
       trigger  date, as well as on each of the n days before the event.  Here
       are some examples:

            REM 6 Jan +5 MSG Remind me of birthday 5 days in advance.

       The above example would be triggered every 6th of January, as  well  as
       the 1st through 5th of January.

       PERIODIC REMINDERS

       We  have  already  seen  some  built-in mechanisms for certain types of
       periodic reminders.  For example, an event  occurring  every  Wednesday
       could be specified as:

            REM Wed MSG Event!

       However,  events  that  do  not repeat daily, weekly, monthly or yearly
       require another approach.  The repeat  component  of  the  REM  command
       fills  this need.  To use it, you must completely specify a date (year,
       month and day, and optionally weekday.)  The  repeat  component  is  an
       asterisk followed by a number specifying the repetition period in days.

       For example, suppose you get paid every second Wednesday, and your last
       payday was Wednesday, 28 October, 1992.  You can use:

            REM 28 Oct 1992 *14 MSG Payday

       This issues the reminder every 14 days, starting  from  the  calculated
       trigger  date.  You can use delta and back with repeat.  Note, however,
       that the back is used only to compute the initial trigger date;  there-
       after,  the  reminder repeats with the specified period.  Similarly, if
       you specify a weekday, it is used only to calculate the  initial  date,
       and does not affect the repetition period.

       SCANFROM and FROM

       The  SCANFROM  and  FROM  keywords  are for advanced Remind programmers
       only, and will be explained in the section "Details about Trigger  Com-
       putation" near the end of this manual.  Note that SCANFROM is available
       only in versions of Remind from 03.00.04 up.  FROM  is  available  only
       from 03.01.00 and later.

       PRIORITY

       The  PRIORITY  keyword must be followed by a number from 0 to 9999.  It
       is used in calendar mode and when sorting reminders.  If two  reminders
       have  the same trigger date and time, then they are sorted by priority.
       If the PRIORITY keyword is not supplied, a default priority of 5000  is
       used.   (This  default  can be changed by adjusting the system variable
       $DefaultPrio.  See the section "System  Variables"  for  more  informa-
       tion.)

       EXPIRY DATES

       Some  reminders  should  be issued periodically for a certain time, but
       then expire.  For example, suppose you have a class every  Friday,  and
       that your last class is on 11 December 1992.  You can use:

            REM Fri UNTIL 11 Dec 1992 MSG Class today.

       Another  example:   Suppose  you  have  jury duty from 30 November 1992
       until 4 December 1992.  The following reminder will issue  the  message
       every day of your jury duty, as well as 2 days ahead of time:

            REM 1992-11-30 *1 +2 UNTIL 1992-12-04 MSG Jury duty

       Note that the repeat of *1 is necessary; without it, the reminder would
       be issued only on 30 November (and the two days preceding.)

       As a special case, you can use the THROUGH keyword instead  of  *1  and
       UNTIL.  The following two REM commands are equivalent:

            REM 1992-11-30 *1 +2 UNTIL 1992-12-04 MSG Jury duty

            REM 1992-11-30 +2 THROUGH 1992-12-04 MSG Jury duty

       THE ONCE KEYWORD

       Sometimes,  it  is necessary to ensure that reminders are run only once
       on a given day.  For example, if you  have  a  reminder  that  makes  a
       backup of your files every Friday:

            REM Fri RUN do_backup

       (Here,  do_backup  is assumed to be a program or shell script that does
       the work.)  If you run Remind from your .login script, for example, and
       log  in  several  times per day, the do_backup program will be run each
       time you log in.   If,  however,  you  use  the  ONCE  keyword  in  the
       reminder,  the  Remind  checks  the  last  access  date of the reminder
       script.  If it is the same as the current date, Remind assumes that  it
       has  already been run, and will not issue reminders containing the ONCE
       keyword.

       Note that if you view or edit your reminder  script,  the  last  access
       date  will  be updated, and the ONCE keyword will not operate properly.
       If you start Remind with the -o option, then the ONCE keyword  will  be
       ignored.

       LOCALLY OMITTING WEEKDAYS

       The OMIT portion of the REM command is used to "omit" certain days when
       counting the delta or back.  It is specified  using  the  keyword  OMIT
       followed  by  a  list of weekdays.  Its action is best illustrated with
       examples:

            REM 1 +1 OMIT Sat Sun MSG Important Event

       This reminder is normally triggered on the first  of  every  month,  as
       well as the day preceding it.  However, if the first of the month falls
       on a Sunday or Monday, then the reminder is triggered starting from the
       previous Friday.  This is because the delta of +1 does not count Satur-
       day or Sunday when it counts backwards from the trigger date to  deter-
       mine how much advance warning to give.

       Contrast  this  with  the  use  of "++1" in the above command.  In this
       case, the reminder is triggered on the first of each month, as well  as
       the day preceding it.  The omitted days are counted.

            REM 1 -1 OMIT Sat Sun MSG Last working day of month

       Again, in the above example, the back of -1 normally causes the trigger
       date to be the last day of the month.  However,  because  of  the  OMIT
       clause,  if  the  first  of  the month falls on a Sunday or Monday, the
       trigger date is moved backwards past the weekend to  Friday.   (If  you
       have  globally  omitted  holidays, the reminder will be moved back past
       them, also.  See "The OMIT command" for more details.)

       By comparison, if we had used "--1", the reminder would be triggered on
       the last day of the month, regardless of the OMIT.

       COMPUTED LOCAL OMITS

       The  OMITFUNC phrase of the REM command allows you to supply a function
       that determines whether or not a date  is  omitted.   The  function  is
       passed  a  single  parameter  of  type DATE, and must return a non-zero
       integer if the date is considered "omitted" and 0 otherwise.  Here's an
       example:

               FSET _third(x) (day(x) % 3) || \
                              (wkdaynum(x) == 0) || \
                              (wkdaynum(x) == 6)
               REM OMITFUNC _third AFTER MSG Working day divisible by 3

       In  the example above, the reminder is triggered every Monday to Friday
       whose day-of-month number is divisible by three.  Here's how it works:

       o      The OMITFUNC _third portion causes all days for which  _third(x)
              returns  non-zero  to  be considered "omitted".  This causes all
              days whose day-of-month number is not a multiple of three to  be
              omitted.   Note that _third also returns non-zero if the weekday
              is Sunday or Saturday.

       o      The AFTER keyword causes the reminder to be moved after a  block
              of omitted days.

       The combination of OMITFUNC and AFTER keyword causes the reminder to be
       issued on all days whose day-of-month number is divisible by three, but
       not on Saturday or Sunday.

       Note  that if you use OMITFUNC, then a local OMIT is ignored as are all
       global OMITs.  If you want to omit specific weekdays, your  omit  func-
       tion will need to test for them specifically.  If you want to take into
       account the global OMIT context, then your omit function will  need  to
       test for that explicitly (using the isomitted() function.)

       Note  that  an incorrect OMITFUNC might cause all days to be considered
       omitted.  For that reason, when Remind searches through  omitted  days,
       it  terminates  the  search after the SATISFY iteration limit (command-
       line option -x.)

       TIMED REMINDERS

       Timed reminders are those that have an AT keyword followed  by  a  time
       and  optional tdelta and trepeat.  The time mau be specified in 24-hour
       format, with 0:00 representing midnight, 12:00 representing  noon,  and
       23:59  representing  one  minute to midnight.  Alternatively, it may be
       specified in common "AM/PM" format; in this case, the hour  must  range
       from  1  to  12.  12:00am represents midnight, 12:00pm represents noon,
       and 11:59pm represents one minute to midnight.  The "am" and "pm"  por-
       tions are case-insensitive and the "m" is optional.

       You  can  use either a colon or a period to separate the hours from the
       minutes.  That is, 13:39 and 13.39 are equivalent.

       Remind treats timed reminders specially.  If the  trigger  date  for  a
       timed  reminder is the same as the current system date, the reminder is
       queued for later activation.  When Remind has finished  processing  the
       reminder  file,  it  puts itself in the background, and activates timed
       reminders when the system time reached the specified time.


       If the trigger date is not the same as the system date, the reminder is
       not queued.

       For  example, the following reminder, triggered every working day, will
       emit a message telling you to leave at 5:00pm:

            REM Mon Tue Wed Thu Fri AT 17:00 MSG Time to leave!

       The following reminder will be triggered on Thursdays and Fridays,  but
       will only be queued on Fridays:

            REM Fri ++1 AT 1:00PM MSG Lunch at 1pm Friday.

       The  tdelta  and  trepeat have the same form as a repeat and delta, but
       are specified in minutes.  For example, this reminder will be triggered
       at 12:00pm as well as 45 minutes before:

            REM AT 12:00 +45 MSG Example

       The  following  will be issued starting at 10:45, every half hour until
       11:45, and again at noon.

            REM AT 12:00 +75 *30 MSG Example2

       The "+75" means that the reminder is issued starting 75 minutes  before
       noon; in other words, at 10:45.  The *30 specifies that the reminder is
       subsequently to be issued every 30 minutes.  Note that the reminder  is
       always issued at the specified time, even if the tdelta is not a multi-
       ple of the trepeat.   So  the  above  example  is  issued  at  10:45am,
       11:15am,  11:45am,  and  12:00pm.  Note that in the time specification,
       there is no distinction between the "+" and "++" forms of tdelta.

       Normally, Remind  will  issue  timed  reminders  as  it  processes  the
       reminder script, as well as queuing them for later.  If you do not want
       Remind to issue the reminders when processing the script, but  only  to
       queue  them  for  later, use the -a command-line option.  If you do not
       want reminders to be queued for later, use the -q command-line option.

       Normally, Remind forks a background process to handle queued reminders.
       If you want Remind to remain in the foreground, use the -f command-line
       option.  This is useful, for example, in .xinitrc  scripts,  where  you
       can use the command:

            remind -fa myreminders &

       This  ensures  that  when  you  exit  X-Windows,  the Remind process is
       killed.

       WARNING ABOUT TIMED REMINDERS

       Note:  If you use user-defined functions or variables (described later)
       in  the  bodies  of  timed reminders, then when the timed reminders are
       activated, the variables and functions have the definitions  that  were
       in effect at the end of the reminder script.  These definitions may not
       necessarily be those that were in effect at the time the  reminder  was
       queued.

       THE SCHED AND WARN KEYWORDS

       The  SCHED  keyword  allows more precise control over the triggering of
       timed reminders, and the WARN keyword allows precise control  over  the
       advance triggering of all types of reminders.  However, discussion must
       be deferred until after  expressions  and  user-defined  functions  are
       explained.  See the subsection "Precise Scheduling" further on.

       TAG AND DURATION

       The  TAG  keyword  lets  you "tag" certain reminders.  This facility is
       used by certain back-ends or systems built around Remind, such as TkRe-
       mind.   These back-ends have specific rules about tags; see their docu-
       mentation for details.

       The TAG keyword is followed by a tag consisting of up to 48 characters.
       You can have as many TAG clauses as you like in a given REM statement.

       If  you  supply the -y option to Remind, then any reminder that lacks a
       TAG will have one synthesized.  The synthesized  tag  consists  of  the
       characters  "__syn__" followed by the hexadecimal representation of the
       MD5 sum of the REM command line.  This lets  you  give  a  more-or-less
       unique identifier to each distinct REM command.

       The DURATION keyword makes sense only for timed reminders; it specifies
       the duration of an event.  For example, if you have a 90-minute meeting
       starting at 1:00pm, you could use any of the following:

            REM 5 March 2021 AT 13:00 DURATION 1:30 MSG Meeting
            REM 5 March 2021 AT 13:00 DURATION 90 MSG Meeting
            REM 5 March 2021 AT 1:00pm DURATION 1:30 MSG Meeting
            REM 5 March 2021 AT 1:00pm DURATION 90 MSG Meeting

       Note  that duration is specified either in hours and minutes as a time,
       or in minutes as an integer.  If you specify a duration of 00:00 or  0,
       then Remind behaves exactly as if no DURATION at all had been present.


THE SUBSTITUTION FILTER
       Before  being  processed, the body of a REM command is passed through a
       substitution filter.  The filter scans for sequences "%x" (where "x" is
       any  letter and certain other characters) and performs substitutions as
       shown below.  (All dates refer to the trigger date of the reminder.)

       %a     is replaced with "on weekday, day month, year"
              For example, consider the reminder:

              REM 18 Oct 1990 +4 MSG Meeting with Bob %a.

              On 16 October 1990, it would print "Meeting with Bob  on  Thurs-
              day, 18 October, 1990."

              On 17 October 1990, it would print "Meeting with Bob tomorrow."

              On 18 October 1990, it would print "Meeting with Bob today."

       %b     is  replaced  with "in diff day's time" where diff is the actual
              number of days between the current date and  the  trigger  date.
              (OMITs have no effect.)
              For example, consider:

              REM 18 Oct 1990 +4 MSG Meeting with Bob %b.

              On  16 October 1990, it would print "Meeting with Bob in 2 days'
              time."

              On 17 October 1990, it would print "Meeting with Bob tomorrow."

              On 18 October 1990, it would print "Meeting with Bob today."

       %c     is replaced with "on weekday"
              Example: REM 18 Oct 1990 +4 MSG Meeting with Bob %c.

              On 16 October 1990, it would print "Meeting with Bob  on  Thurs-
              day."

              On 17 October 1990, it would print "Meeting with Bob tomorrow."

              On 18 October 1990, it would print "Meeting with Bob today."

       %d     is replaced with "day", the day of the month.

       %e     is replaced with "on dd-mm-yyyy"

       %f     is replaced with "on mm-dd-yyyy"

       %g     is replaced with "on weekday, day month"

       %h     is replaced with "on dd-mm"

       %i     is replaced with "on mm-dd"

       %j     is  replaced  with  "on  weekday, month day-th, year"  This form
              appends the characters "st", "nd", "rd" or "th" to  the  day  of
              the month, as appropriate.

       %k     is replaced with "on weekday, month day-th"

       %l     is replaced with "on yyyy-mm-dd"

       %m     is replaced with "month", the name of the month.

       %n     is replaced with the number (1 to 12) of the month.

       %o     is  replaced  with  " (today)" if and only if the current system
              date is the same as the date being used by Remind as the current
              date.   Recall  that you can specify a date for Remind to use on
              the command line.  This substitution is not generally useful  in
              a  REM  command,  but  is useful in a BANNER command.  (See "The
              BANNER Command.")

       %p     is replaced with "s" if the diff between the  current  date  and
              the  trigger  date  is  not  1.   You  can use this to construct
              reminders like:
              REM 1 Jan +4 MSG %x day%p to go before New Year!

       %q     is replaced with "'s" if the diff between the trigger  date  and
              the  current  date  is  1.   Otherwise, it is replaced with "s'"
              This can be used as follows:
              REM 1 Jan +4 MSG New Year in %x day%q time!

       %r     is replaced with the day of the month (01 to 31) padded  with  a
              leading zero if needed to pad to two digits.

       %s     is  replaced  with "st", "nd", "rd" or "th" depending on the day
              of the month.

       %t     is replaced with the number of the month (01 to  12)  padded  to
              two digits with a leading zero.

       %u     is replaced with "on weekday, day-th month, year"  This is simi-
              lar to %a except that "st", "nd", "rd" or "th" is added  to  the
              day as appropriate.

       %v     is replaced with "on weekday, day-th month"

       %w     is replaced with "weekday", the name of the day of the week.

       %x     is replaced with the diff between the current date and the trig-
              ger date.  The diff is defined as  the  actual  number  of  days
              between  these  two  dates; OMITs are not counted.  (Strict date
              subtraction is performed.)

       %y     is replaced with "year", the year of the trigger date.

       %z     is replaced with "yy", the last two digits of the year.

       %_     (percent-underscore) is replaced with a newline.   You  can  use
              this to achieve multi-line reminders.

       %1     is  replaced  with "now", "m minutes from now", "m minutes ago",
              "h hours from now", "h hours ago", "h hours and m  minutes  from
              now"  or "h hours and m minutes ago", as appropriate for a timed
              reminder.  Note that unless you specify  the  -a  option,  timed
              reminders  will  be  triggered like normal reminders, and thus a
              timed reminder that occurred earlier in the  day  may  be  trig-
              gered.  This causes the need for the "...ago" forms.

       %2     is replaced with "at hh:mmam" or "..pm" depending on the AT time
              of the reminder.

       %3     is replaced with "at hh:mm" in 24-hour format.

       %4     is replaced with "mm" where mm is the number of minutes  between
              "now"  and  the time specified by AT.  If the AT time is earlier
              than the current time, then the result is negative.

       %5     is replaced with "ma" where ma is the absolute value of the num-
              ber produced by %4.

       %6     is replaced with "ago" or "from now", depending on the relation-
              ship between the AT time and the current time.

       %7     is replaced with the number of hours between the AT time and the
              current time.  It is always non-negative.

       %8     is  replaced  with the number of minutes between the AT time and
              the current time, after the hours (%7) have been subtracted out.
              This is a number ranging from 0 to 59.

       %9     is replaced with "s" if the value produced by %8 is not 1.

       %0     is replaced with "s" if the value produced by %7 is not 1.

       %!     is replaced with "is" if the current time is before the AT time,
              or "was" if it is after.

       %@     is similar to %2 but displays the current time.

       %#     is similar to %3 but displays the current time.

       %"     (percent-doublequote - ") is removed.  This sequence is not used
              by  the  substitution  filter,  but is used to tell Remind which
              text to include in a calendar entry when the -c, -s or -p option
              is chosen.  See "Calendar Mode"

       Notes:

       o      Remind  normally prints a blank line after each reminder; if the
              last character of the body is "%", the blank line  will  not  be
              printed.

       o      Substitutions  a,  b, c, e, f, g, h, i, j, k, l, u and v all are
              replaced with "today" if the current  date  equals  the  trigger
              date,  or  "tomorrow"  if  the trigger date is one day after the
              current date.  Thus, they are  not  the  same  as  substitutions
              built up from the simpler %w, %y, etc.  sequences.

       o      Any of the substitutions dealing with time (0 through 9 and '!')
              produce undefined results if used in a reminder  that  does  not
              have  an AT keyword.  Also, if a reminder has a delta and may be
              triggered on several days, the  time  substitutions  ignore  the
              date.  Thus, the %1 substitution may report that a meeting is in
              15 minutes, for example, even though it may only be  in  2  days
              time,  because a delta has triggered the reminder.  It is recom-
              mended that  you  use  the  time  substitutions  only  in  timed
              reminders with no delta that are designed to be queued for timed
              activation.

       o      Capital letters can be used in  the  substitution  sequence,  in
              which case the first character of the substituted string is cap-
              italized (if it is normally a lower-case letter.)

       o      All other characters following a "%" sign are simply copied.  In
              particular,  to  get  a  "%" sign out, use "%%" in the body.  To
              start the body of a reminder with  a  space,  use  "%  ",  since
              Remind  normally scans for the first non-space character after a
              MSG, CAL or RUN token.

THE OMIT COMMAND
       In addition to being a keyword in the REM command, OMIT is a command in
       its own right.  Its syntax is:

              OMIT day month [year]

              or:

              OMIT day1 month1 year1 THROUGH day2 month2 year2

       The OMIT command is used to "globally" omit certain days (usually holi-
       days).  These globally-omitted days are skipped  by  the  "-"  and  "+"
       forms of back and delta.  Some examples:

            OMIT 1 Jan
            OMIT 7 Sep 1992

       The first example specifies a holiday that occurs on the same date each
       year - New Year's Day.  The second example  specifies  a  holiday  that
       changes  each year - Labour Day.  For these types of holidays, you must
       create an OMIT command for each year.  (Later, in  the  description  of
       expressions  and some of the more advanced features of Remind, you will
       see how to automate this for some cases.)

       As with the REM command, you can use shorthand  specifiers  for  dates;
       the following are equivalent:

            OMIT 7 Sep 1992
            OMIT 1992-09-07

       For convenience, you can use a delta and MSG or RUN keyword in the OMIT
       command.  The following sequences are equivalent:

            OMIT 1 Jan
            REM 1 Jan +4 MSG New year's day is %b!

            and

            OMIT 1 Jan +4 MSG New year's day is %b!

       The THROUGH keyword lets you conveniently OMIT a range  of  days.   The
       starting  and  ending  points  must  be  fully-specified (ie, they must
       include day, month and year.).  For example,  the  following  sequences
       are equivalent:

            OMIT 3 Jan 2011
            OMIT 4 Jan 2011
            OMIT 5 Jan 2011

            and

            OMIT 3 Jan 2011 THROUGH 5 Jan 2011

       You can make a THROUGH OMIT do double-duty as a REM command:

            OMIT 6 Sep 2010 THROUGH 10 Sep 2010 MSG Vacation


       You can debug your global OMITs with the following command:

            OMIT DUMP

       The  OMIT DUMP command prints the current global omits to standard out-
       put.

       THE BEFORE, AFTER AND SKIP KEYWORDS

       Normally, days that are omitted, whether by a global  OMIT  command  or
       the local OMIT or OMITFUNC keywords in a REM statement, only affect the
       counting of the -back or the +delta.  For example, suppose you  have  a
       meeting  every Wednesday.  Suppose, too, that you have indicated 11 Nov
       as a holiday:

            OMIT 11 Nov +4 MSG Remembrance Day
            REM Wed +1 MSG Code meeting %b.

       The above sequence will issue a reminder about a meeting for 11  Novem-
       ber 1992, which is a Wednesday.  This is probably incorrect.  There are
       three options:

       BEFORE This keyword moves the reminder  to  before  any  omitted  days.
              Thus,  in the above example, use of BEFORE would cause the meet-
              ing reminder to be triggered on Tuesday, 10 November 1992.

       AFTER  This keyword moves the reminder to after any omitted  days.   In
              the  above  example,  the meeting reminder would be triggered on
              Thursday, 12 November 1992.

       SKIP   This keyword causes the reminder to be skipped completely on any
              omitted  days.   Thus,  in the above example, the reminder would
              not be triggered on 11 November  1992.   However,  it  would  be
              triggered as usual on the following Wednesday, 18 November 1992.

       The  BEFORE  and  AFTER keywords move the trigger date of a reminder to
       before or after a block of omitted  days,  respectively.   Suppose  you
       normally  run  a backup on the first day of the month.  However, if the
       first day of the month is a weekend or holiday, you run the  backup  on
       the first working day following the weekend or holiday.  You could use:

            REM 1 OMIT Sat Sun AFTER RUN do_backup

       Let's  examine  how  the trigger date is computed.  The 1 specifies the
       first day of the month.  The local OMIT keyword causes the  AFTER  key-
       word  to  move  the reminder forward past weekends.  Finally, the AFTER
       keyword will keep moving the reminder forward until it has  passed  any
       holidays specified with global OMIT commands.

THE INCLUDE COMMAND
       Remind allows you to include other files in your reminder script, simi-
       lar to the C preprocessor #include directive.  For example, your system
       administrator may maintain a file of holidays or system-wide reminders.
       You can include these in your reminder script as follows:

            INCLUDE /usr/share/remind/holidays
            INCLUDE /usr/share/remind/reminders

       (The actual pathnames vary from system to  system  -  ask  your  system
       administrator.)

       INCLUDE files can be nested up to a depth of 8.

       If  you  specify  a filename of "-" in the INCLUDE command, Remind will
       begin reading from standard input.

       If you specify a directory as the argument to INCLUDE, then Remind will
       process  all  files  in  that  directory  that  match the shell patterm
       "*.rem".  The files are processed  in  sorted  order;  the  sort  order
       matches that used by the shell when it expands "*.rem".


THE RUN COMMAND
       If  you include other files in your reminder script, you may not always
       entirely trust the contents of the other files.  For example, they  may
       contain  RUN-type  reminders that could be used to access your files or
       perform undesired actions.  The RUN command can restrict this:  If  you
       include  the  command  RUN  OFF  in your top-level reminder script, any
       reminder or expression that would normally execute a system command  is
       disabled.   RUN  ON  will  re-enable  the execution of system commands.
       Note that the RUN ON  command  can  only  be  used  in  your  top-level
       reminder  script; it will not work in any files accessed by the INCLUDE
       command.  This is to protect you from someone placing a RUN ON  command
       in  an  included file.  However, the RUN OFF command can be used at top
       level or in an included file.

       If you run Remind with the -r command-line option,  RUN-type  reminders
       and  the  shell() function will be disabled, regardless of any RUN com-
       mands in the reminder script.  However, any command supplied  with  the
       -k option will still be executed.

       One  use  of  the  RUN command is to provide a secure interface between
       Remind and the Elm mail system.  The Elm system can automatically  scan
       incoming  mail for reminder or calendar entries, and place them in your
       calendar file.  To use this feature, you should set the calendar  file-
       name  option under Elm to be something like "~/.reminders.in", not your
       main reminder file!  This is so that any RUN ON commands mailed to  you
       can never be activated.

       Then,  you can use the Elm scan message for calendar entries command to
       place reminders prefaced by "->"  into  .reminders.in.   In  your  main
       .reminders file, include the following lines:

            RUN OFF   # Disable RUN
            INCLUDE .reminders.in
            RUN ON    # Re-enable RUN

       In  addition,  Remind  contains a few other security features.  It will
       not read a file that is group- or world-writable.  It will not run set-
       uid.   If  it  reads  a file you don't own, it will disable RUN and the
       shell() function.  And if it is run as root, it will  only  read  files
       owned by root.

THE BANNER COMMAND
       When Remind first issues a reminder, it prints a message like this:

            Reminders for Friday, 30th October, 1992 (today):

       (The  banner is not printed if any of the calendar-producing options is
       used, or if the -k option is used.)

       The BANNER command lets you change the format.  It should appear before
       any REM commands.  The format is:

              BANNER format

       The  format  is  similar  to  the  body of a REM command.  It is passed
       through the substitution filter, with an implicit trigger of  the  cur-
       rent system date.  Thus, the default banner is equivalent to:

            BANNER Reminders for %w, %d%s %m, %y%o:

       You can disable the banner completely with BANNER %.  Or you can create
       a custom banner:

            BANNER Hi - here are your reminders for %y-%t-%r:

CONTROLLING THE OMIT CONTEXT
       Sometimes, it is necessary to temporarily change the global OMITs  that
       are in force for a few reminders.  Three commands allow you to do this:

       PUSH-OMIT-CONTEXT
              This  command  saves  the  current  global  OMITs on an internal
              stack.

       CLEAR-OMIT-CONTEXT
              This command clears all of the global OMITs,  starting  you  off
              with a "clean slate."

       POP-OMIT-CONTEXT
              This  command  restores  the global OMITs that were saved by the
              most recent PUSH-OMIT-CONTEXT.

       For example, suppose you have a block of reminders that require a clear
       OMIT  context,  and that they also introduce unwanted global OMITs that
       could interfere with later reminders.   You  could  use  the  following
       fragment:

            PUSH-OMIT-CONTEXT   # Save the current context
            CLEAR-OMIT-CONTEXT  # Clean the slate
            # Block of reminders goes here
            POP-OMIT-CONTEXT    # Restore the saved omit context

EXPRESSIONS
       In  certain contexts, to be described later, Remind will accept expres-
       sions for evaluation.  Remind expressions resemble C  expressions,  but
       operate on different types of objects.

       DATA TYPES

       Remind expressions operate on five types of objects:

       INT    The  INT data type consists of the integers representable in one
              machine word.  The INT data type  corresponds  to  the  C  "int"
              type.

       STRING The  STRING  data type consists of strings of characters.  It is
              somewhat comparable to a C character  array,  but  more  closely
              resembles the string type in BASIC.

       TIME   The  TIME data type consists of times of the day.  The TIME data
              type is internally stored as an integer representing the  number
              of minutes since midnight.

       DATE   The  DATE  data  type  consists  of  dates (later than 1 January
              1990.)  Internally, DATE objects are stored  as  the  number  of
              days since 1 January 1990.

       DATETIME
              The  DATETIME  data  type  consists of a date and time together.
              Internally, DATETIME objects are stored as the number of minutes
              since  midnight,  1  January  1990.  You can think of a DATETIME
              object as being the combination of DATE and TIME parts.

       CONSTANTS

       The following examples illustrate constants in Remind expressions:

       INT constants
              12, 36, -10, 0, 1209

       STRING constants
              "Hello there", "This is a test", "\n\gosd\w", ""

              Note that the empty string is represented by "", and that  back-
              slashes  in  a  string are not interpreted specially, as in they
              are in C.

       TIME constants
              12:33, 0:01, 14:15, 16:42, 12.16, 13.00, 1.11, 4:30PM, 12:20am

              Note that TIME constants may be written in 24-hour format or  in
              common "AM/PM" format.  If you use "AM/PM" format, then the hour
              can range from 1 to 12.  Either a period or colon can be used to
              separate  the minutes from the hours.  However, Remind will con-
              sistently output times in 24-hour format using only one  separa-
              tor  character.   (The  output  separator character is chosen at
              compile-time.)

       DATE constants
              DATE constants are expressed as  'yyyy/mm/dd'  or  'yyyy-mm-dd',
              and the single quotes must be supplied.  This distinguishes date
              constants from division or subtraction of integers.  Examples:

              '1993/02/22', '1992-12-25', '1999/01/01'

              Note that DATE values are printed without the quotes.   Although
              either '-' or '/' is accepted as a date separator on input, when
              dates are printed, only one will be used.  The choice of whether
              to  use '-' or '/' is made at compile-time.  Note also that ver-
              sions of Remind prior to 03.00.01  did  not  support  date  con-
              stants.   In  those  versions,  you  must create dates using the
              date() function.  Also, versions prior to 03.00.02 did not  sup-
              port the '-' date separator.

       DATETIME constants
              DATETIME  constants  are  expressed  similarly to DATE constants
              with the addition of an "@HH:MM" part,  optionally  followed  by
              "am" or "pm".  For example:

              '2008-04-05@23:11',    '1999/02/03@14:06',   '2001-04-07@08:30',
              '2020-01-01@3:20pm'

              DATETIME values are printed without  the  quotes.   Notes  about
              date  and  time separator characters for DATE and TIME constants
              apply also to DATETIME constants.

       OPERATORS

       Remind has the following operators.  Operators on the  same  line  have
       equal  precedence, while operators on lower lines have lower precedence
       than those on higher lines.  The operators approximately correspond  to
       C operators.

            !  -     (unary logical negation and arithmetic negation)
            *  /  %
            +  -
            <  <=  >  >=
            ==  !=
            &&
            ||

       DESCRIPTION OF OPERATORS

       !      Logical  negation.  Can be applied to an INT type.  If the oper-
              and is non-zero, returns zero.  Otherwise, returns 1.

       -      Unary minus.  Can be applied to an INT.  Returns the negative of
              the operand.

       *      Multiplication.  Returns the product of two INTs.

       /      Integer  division.  Returns the quotient of two INTs, discarding
              the remainder.

       %      Modulus.   Returns  the  remainder  upon  dividing  one  INT  by
              another.

       +      Has several uses.  These are:

              INT + INT - returns the sum of two INTs.

              INT + TIME or TIME + INT - returns a TIME obtained by adding INT
              minutes to the original TIME.  The result will always range from
              00:00 through 23:59.

              TIME + TIME treats the second TIME parameter as a duration, con-
              verting it to an integer number of minutes  past  midnight,  and
              then performs addition as with TIME + INT.

              INT + DATE or DATE + INT - returns a DATE obtained by adding INT
              days to the original DATE.

              INT + DATETIME or DATETIME + INT - returns a  DATETIME  obtained
              by adding INT minutes to the original DATETIME.

              DATETIME  + TIME or TIME + DATETIME treats the TIME parameter as
              a duration, converting it to an integer number of  minutes  past
              midnight, and then performs addition as with DATETIME + INT.

              STRING  + STRING - returns a STRING that is the concatenation of
              the two original STRINGs.

              STRING + anything or anything + STRING - converts the non-STRING
              argument  to a STRING, and then performs concatenation.  See the
              coerce() function.

       -      Has several uses.  These are:

              INT - INT - returns the difference of two INTs.

              DATE - DATE - returns (as an INT) the difference in days between
              two DATEs.

              TIME  -  TIME  -  returns  (as an INT) the difference in minutes
              between two TIMEs.

              DATETIME - DATETIME - returns (as an INT) the difference in min-
              utes between two DATETIMEs.

              DATE  -  INT  - returns a DATE that is INT days earlier than the
              original DATE.

              TIME - INT - returns a TIME that is INT minutes earlier than the
              original TIME.

              DATETIME  - INT - returns a DATETIME that is INT minutes earlier
              than the original DATETIME.

              DATETIME - TIME - coerces the TIME to an INT and  then  performs
              subtraction as above.

       <, <=, >, and >=
              These  are  the comparison operators.  They can take operands of
              any type, but both operands must be of the same type.  The  com-
              parison operators return 1 if the comparison is true, or 0 if it
              is false.  Note that string comparison  is  done  following  the
              lexical  ordering  of  characters on your system, and that upper
              and lower case are distinct for these operators.

       ==, != == tests for equality, returning 1 if its  operands  are  equal,
              and 0 if they are not.  != tests for inequality.

              If  the  operands  are not of the same type, == returns 0 and !=
              returns 1.  Again, string comparisons are case-sensitive.

       &&     This is the logical AND operator.  Both of its operands must  be
              of  type INT.  It returns 1 if both operands are non-zero, and 0
              otherwise.

       ||     This is the logical OR operator.  Both of its operands  must  be
              of  type INT.  It returns 1 if either operand is non-zero, and 0
              otherwise.

       NOTES

       Operators of equal precedence are always evaluated from left to  right,
       except where parentheses dictate otherwise.  This is important, because
       the enhanced "+" operator is not necessarily associative.  For example:

            1 + 2 + "string" + 3 + 4  yields "3string34"
            1 + (2 + "string") + (3 + 4)  yields "12string7"
            12:59 + 1 + "test"  yields "13:00test"
            12:59 + (1 + "test")  yields "12:591test"

       The logical operators are not  so-called  short-circuit  operators,  as
       they  are  in C.  Both operands are always evaluated.  Thus, an expres-
       sion such as:

            (f!=0) && (100/f <= 3)

       will cause an error if f is zero.

       VARIABLES

       Remind allows you to assign values to variables.  The  SET  command  is
       used as follows:

       SET var expr

       Var  is  the name of a variable.  It must start with a letter or under-
       score, and consist only of letters, digits and underscores.   Only  the
       first 12 characters of a variable name are significant.  Variable names
       are not case sensitive; thus, "Afoo" and "afOo" are the same  variable.
       Examples:

            SET a 10 + (9*8)
            SET b "This is a test"
            SET mydir getenv("HOME")
            SET time 12:15
            SET date today()

       Note  that variables themselves have no type.  They take on the type of
       whatever you store in them.

       To delete a variable, use the UNSET command:

       UNSET var [var...]

       For example, to delete all the variables declared above, use:

            UNSET a b mydir time date

       SYSTEM VARIABLES

       In addition to the regular user variables, Remind has  several  "system
       variables"  that  are  used  to query or control the operating state of
       Remind.  System variables are available starting from version  03.00.07
       of Remind.

       All system variables begin with a dollar sign '$'.  They can be used in
       SET commands and expressions just as regular variables can.  All system
       variables  always  hold  values of a specified type.  In addition, some
       system variables cannot be modified, and you cannot create  new  system
       variables.   System  variables  can  be initialized on the command line
       with the -i option, but you may need to quote them to avoid having  the
       shell  interpret  the dollar sign.  System variable names are not case-
       sensitive.

       The following system variables are defined.  Those  marked  "read-only"
       cannot be changed with the SET command.  All system variables hold val-
       ues of type INT, unless otherwise specified.

       $CalcUTC
              If 1 (the default), then Remind uses C library functions to cal-
              culate  the  number  of minutes between local and Universal Time
              Coordinated.  This affects astronomical calculations  (sunrise()
              for  example.)  If 0, then you must supply the number of minutes
              between local and Universal Time Coordinated in the $MinsFromUTC
              system variable.

       $CalMode (read-only)
              If  non-zero,  then  the  -c  option was supplied on the command
              line.

       $Daemon (read-only)
              If the daemon mode -z was invoked, contains the number  of  min-
              utes  between  wakeups.  If not running in daemon mode, contains
              0.

       $DateSep
              This variable can be set only to "/" or "-".  It holds the char-
              acter  used  to separate portions of a date when Remind prints a
              DATE or DATETIME value.

       $DefaultColor
              This variable can be set to a string that has the form of  three
              space-separated  numbers.  Each number must be an integer from 0
              to 255, or all three numbers must be -1.  The default  value  of
              $DefaultColor  is  "-1 -1 -1", which suppresses default coloring
              of MSG-type reminders.  If you set $DefaultColor  to  any  other
              value,  then  all  MSG-,  MSF- and CAL-type reminders are effec-
              tively converted into SPECIAL COLOR reminders whose color  value
              is specified by $DefaultColor.

              Unlike other system variables, the value of $DefaultColor is not
              preserved between calendar iterations; rather, it  is  reset  to
              "-1 -1 -1" at the start of each iteration.

       $DefaultPrio
              The  default  priority  assigned to reminders without a PRIORITY
              clause.  You can set this as required to adjust  the  priorities
              of  blocks  of  reminders  without having to type priorities for
              individual reminders.  At startup, $DefaultPrio is set to  5000;
              it can range from 0 to 9999.

       $DontFork (read-only)
              If  non-zero,  then  the  -c  option was supplied on the command
              line.

       $DontTrigAts (read-only)
              The number of times that the -a option was supplied on the  com-
              mand line.

       $DontQueue (read-only)
              If  non-zero,  then  the  -q  option was supplied on the command
              line.

       $EndSent (STRING type)
              Contains a list of characters that end a sentence.  The MSF key-
              word  inserts  two  spaces  after  these characters.  Initially,
              $EndSent is set to ".!?" (period, exclamation mark, and question
              mark.)

       $EndSentIg (STRING type)
              Contains  a  list  of characters that should be ignored when MSF
              decides whether or not to place two  spaces  after  a  sentence.
              Initially,  is  set  to "'>)]}"+CHAR(34) (single-quote, greater-
              than, right parenthesis, right bracket, right brace, and double-
              quote.)

              For example, the default values work as follows:

                   MSF He said, "Huh! (Two spaces will follow this.)"  Yup.

              because  the  final  parenthesis  and quote are ignored (for the
              purposes of spacing) when they follow a period.

       $FirstIndent
              The number of spaces by which to indent the first line of a MSF-
              type reminder.  The default is 0.

       $FoldYear
              The  standard Unix library functions may have difficulty dealing
              with dates later than 2037.  If this variable is set to 1,  then
              the  UTC  calculations  "fold back" years later than 2037 before
              using the Unix library functions.   For  example,  to  find  out
              whether  or not daylight saving time is in effect in June, 2077,
              the year is "folded back" to 2010, because both years begin on a
              Monday, and both are non-leapyears.  The rules for daylight sav-
              ing time are thus presumed to be identical for both  years,  and
              the  Unix  library  functions can handle 2010.  By default, this
              variable is 0.  Set it to 1 if the sun or UTC  functions  misbe-
              have for years greater than 2037.

       $FormWidth
              The  maximum  width of each line of text for formatting MSF-type
              reminders.  The default is the width of the terminal in columns,
              minus  8,  but  clamped at a minimum of 20 and a maximum of 500.
              If standard output is not a terminal, then the default is  72.If
              an  MSF-type  reminder  contains  a word too long to fit in this
              width, it will not be  truncated  -  the  width  limit  will  be
              ignored.

       $HushMode (read-only)
              If  non-zero,  then  the  -h  option was supplied on the command
              line.

       $IgnoreOnce (read-only)
              If non-zero, then the -o option  was  supplied  on  the  command
              line,  or  a date different from today's true date was supplied.
              If non-zero, then ONCE directives will be ignored.

       $InfDelta (read-only)
              If non-zero, then the -t option  was  supplied  on  the  command
              line.

       $LatDeg, $LatMin, $LatSec
              These  specify the latitude of your location.  $LatDeg can range
              from -90 to 90, and the others from -59 to 59.   Northern  lati-
              tudes  are  positive;  southern ones are negative.  For southern
              latitudes, all three components should be negative.

       $Location (STRING type)
              This is a string specifying the name of your  location.   It  is
              usually  the  name of your town or city.  It can be set to what-
              ever you like, but good style indicates that it should  be  kept
              consistent with the latitude and longitude system variables.

       $LongDeg, $LongMin, $LongSec
              These  specify  the  longitude  of  your location.  $LongDeg can
              range from -180 to 180.  Western longitudes are positive;  east-
              ern  ones  are  negative.  Note that all three components should
              have the same sign: All positive for Western longitudes and  all
              negative for Eastern longitudes.

              The latitude and longitude information is required for the func-
              tions sunrise() and sunset().  Default values  can  be  compiled
              into  Remind,  or you can SET the correct values at the start of
              your reminder scripts.

       $MaxSatIter
              The  maximum  number  of  iterations  for  the  SATISFY   clause
              (described later.)  Must be at least 10.

       $MaxStringLen
              A limit on the longest string that Remind will allow you to cre-
              ate.  The default is 65535.

       $MinsFromUTC
              The number of minutes between  Universal  Time  Coordinated  and
              local  time.   If  $CalcUTC is non-zero, this is calculated upon
              startup of Remind.  Otherwise, you must set it  explicitly.   If
              $CalcUTC  is zero, then $MinsFromUTC is used in the astronomical
              calculations.  You must adjust it for daylight saving time your-
              self.  Also, if you want to initialize $MinsFromUTC using the -i
              command-line option, you must also set $CalcUTC to 0 with the -i
              option.

       $NextMode (read-only)
              If  non-zero,  then  the  -n  option was supplied on the command
              line.

       $NumQueued (read-only)
              Contains the number of reminders queued so  far  for  background
              timed triggering.

       $NumTrig (read-only)
              Contains the number of reminders triggered for the current date.
              One use for this variable is as follows:  Suppose  you  wish  to
              shade  in the box of a PostScript calendar whenever a holiday is
              triggered.  You could save the value of $NumTrig  in  a  regular
              variable  prior  to  executing a block of holiday reminders.  If
              the value of $NumTrig after the holiday block  is  greater  than
              the  saved  value,  then at least one holiday was triggered, and
              you can execute the command to shade in the calendar box.   (See
              the section "Calendar Mode".)

              Note that $NumTrig is affected only by REM commands; triggers in
              IFTRIG commands do not affect it.

       $PrefixLineNo (read-only)
              If non-zero, then the -l option  was  supplied  on  the  command
              line.

       $PSCal (read-only)
              If  non-zero,  then  the  -p  option was supplied on the command
              line.

       $RunOff (read-only)
              If non-zero, the RUN directives are disabled.

       $SimpleCal (read-only)
              Set to a non-zero value if either of the -p or  -s  command-line
              options was supplied.

       $SortByDate (read-only)
              Set  to  0  if  no  -g  option  is used, 1 if sorting by date in
              ascending order, or 2 if sorting by date in descending order.

       $SortByPrio (read-only)
              Set to 0 if no -g option is used, 1 if sorting  by  priority  in
              ascending  order,  or  2  if  sorting  by priority in descending
              order.

       $SortByTime (read-only)
              Set to 0 if no -g option is  used,  1  if  sorting  by  time  in
              ascending order, or 2 if sorting by time in descending order.

       $SubsIndent
              The number of spaces by which all lines (except the first) of an
              MSF-type reminder should be indented.  The default is 0.

       $T (read-only, DATE type)
              Exactly equivalent to trigdate().  (See BUILT-IN FUNCTIONS.)

       $Td (read-only)
              Equivalent to day(trigdate()).

       $Tm (read-only)
              Equivalent to monnum(trigdate()).

       $Tw (read-only)
              Equivalent to wkdaynum(trigdate()).

       $Ty (read-only)
              Equivalent to year(trigdate()).

       $TimeSep
              This variable can be set only to ":" or ".".  It holds the char-
              acter  used  to separate portions of a time when Remind prints a
              TIME or DATETIME value.

       $UntimedFirst (read-only)
              Set to 1 if the -g option is used with a fourth  sort  character
              of "d"; set to 0 otherwise.

       $U (read-only, DATE type)
              Exactly equivalent to today().  (See BUILT-IN FUNCTIONS.)

       $Ud (read-only)
              Equivalent to day(today()).

       $Um (read-only)
              Equivalent to monnum(today()).

       $Uw (read-only)
              Equivalent to wkdaynum(today()).

       $Uy (read-only)
              Equivalent to year(today()).

       Note:   If  any of the calendar modes are in effect, then the values of
       $Daemon, $DontFork, $DontTrigAts, $DontQueue,  $HushMode,  $IgnoreOnce,
       $InfDelta, and $NextMode are not meaningful.

       BUILT-IN FUNCTIONS

       Remind has a plethora of built-in functions.  The syntax for a function
       call is the same as in C - the function name,  followed  a  comma-sepa-
       rated  list  of arguments in parentheses.  Function names are not case-
       sensitive.  If a function takes no arguments, it must  be  followed  by
       "()"  in  the  function call.  Otherwise, Remind will interpret it as a
       variable name, and probably not work correctly.

       In the descriptions below, short forms are used  to  denote  acceptable
       types  for  the  arguments.   The characters "i", "s", "d", "t" and "q"
       denote INT, STRING, DATE, TIME and  DATETIME  arguments,  respectively.
       If an argument can be one of several types, the characters are concate-
       nated.  For example, "di_arg" denotes an argument that can be a DATE or
       an INT.  "x_arg" denotes an argument that can be of any type.  The type
       of the argument is followed by an underscore and an  identifier  naming
       the argument.

       The built-in functions are:

       abs(i_num)
              Returns the absolute value of num.

       access(s_file, si_mode)
              Tests  the  access permissions for the file file.  Mode can be a
              string, containing a mix of the characters "rwx" for read, write
              and  execute  permission  testing.  Alternatively, mode can be a
              number as described in the  UNIX  access(2)  system  call.   The
              function  returns  0 if the file can be accessed with the speci-
              fied mode, and -1 otherwise.

       adawn([dq_date])
              Returns the time of "astronomical dawn" on the  specified  date.
              If  date  is omitted, defaults to today().  If a datetime object
              is supplied, only the date component is used.

       adusk([dq_date])
              Returns the time of "astronomical  twilight"  on  the  specified
              date.  If date is omitted, defaults to today().

       ampm(tq_time [,s_am [,s_pm]])
              Returns a STRING that is the result of converting time (which is
              either a TIMEor a  DATETIME  object)  to  "AM/PM"  format.   The
              optional arguments am and pm are the strings to append in the AM
              and PM case, respectively; they default to "AM" and  "PM".   The
              function  obeys  the  system  variables  $DateSep,  $TimeSep and
              $DateTimeSep when formatting its output.  For example:

                      ampm(0:22)                 returns "12:22AM"
                      ampm(17:45, "am", "pm")    returns "5:45pm"
                      ampm('2020-03-14@21:34')   returns "2020-03-14@9:34PM"

       args(s_fname)
              Returns the number of arguments  expected  by  the  user-defined
              function  fname,  or -1 if no such user-defined function exists.
              Note that this function examines  only  user-defined  functions,
              not built-in functions.  Its main use is to determine whether or
              not a particular user-defined function has been  defined  previ-
              ously.   The  args()  function  is available only in versions of
              Remind from 03.00.04 and up.

       asc(s_string)
              Returns an INT that is the ASCII code of the first character  in
              string.  As a special case, asc("") returns 0.

       baseyr()
              Returns  the "base year" that was compiled into Remind (normally
              1990.)  All dates are stored internally as the  number  of  days
              since 1 January of baseyr().

       char(i_i1 [,i_i2...])
              This  function can take any number of INT arguments.  It returns
              a STRING consisting of the characters  specified  by  the  argu-
              ments.   Note  that none of the arguments can be 0, unless there
              is only one argument.  As a special case, char(0) returns "".

              Note that because Remind does not support escaping of characters
              in strings, the only way to get a double-quote in a string is to
              use char(34).

       choose(i_index, x_arg1 [,x_arg2...])
              Choose must take at least two arguments, the first of  which  is
              an  INT.   If  index  is  n, then the nth subsequent argument is
              returned.  If index is less than 1, then arg1 is  returned.   If
              index  is  greater than the number of subsequent arguments, then
              the last argument is returned.  Examples:

                 choose(0, "foo", 1:13, 1000) returns "foo"
                 choose(1, "foo", 1:13, 1000) returns "foo"
                 choose(2, "foo", 1:13, 1000) returns 1:13
                 choose(3, "foo", 1:13, 1000) returns 1000
                 choose(4, "foo", 1:13, 1000) returns 1000
              Note that all arguments to choose() are always evaluated.

       coerce(s_type, x_arg)
              This function converts arg to the specified type, if  such  con-
              version  is  possible.   Type  must  be  one of "INT", "STRING",
              "DATE", "TIME" or "DATETIME" (case-insensitive).  The conversion
              rules are as follows:

              If  arg  is  already  of  the  type  specified,  it  is returned
              unchanged.

              If type is "STRING", then arg is converted to a string  consist-
              ing of its printed representation.

              If  type is "DATE", then an INT arg is converted by interpreting
              it as the number of days since 1 January baseyr().  A STRING arg
              is  converted  by  attempting to read it as if it were a printed
              date.  A DATETIME is converted to a date by  dropping  the  time
              component.  A TIME arg cannot be converted to a date.

              If  type is "TIME", then an INT arg is converted by interpreting
              it as the number of minutes since midnight.   A  STRING  arg  is
              converted by attempting to read it as if it were a printed time.
              A DATETIME is converted to a time by dropping  the  date  compo-
              nent.  A DATE arg cannot be converted to a time.

              If  type  is  "DATETIME", then an INT arg is converted by inter-
              preting it as the number of minutes since  midnight,  1  January
              baseyr().   A STRING is converted by attempting to read it as if
              it were a printed datetime.  Other types cannot be converted  to
              a datetime.

              If  type  is  "INT",  then DATE, TIME and DATETIME arguments are
              converted using the reverse of procedures  described  above.   A
              STRING arg is converted by parsing it as an integer.

       current()
              Returns  the  current  date and time as a DATETIME object.  This
              may be the actual date and time, or may be  the  date  and  time
              supplied on the command line.

       date(i_y, i_m, i_d)
              The  date()  function returns a DATE object with the year, month
              and day components specified by y, m and d.

       datepart(dq_datetime)
              Returns a DATE object representing the date portion of datetime.

       datetime(args)
              The datetime() function can take anywhere from two to five argu-
              ments.   It  always  returns a DATETIME generated from its argu-
              ments.

              If you supply two arguments, the first must be a  DATE  and  the
              second a TIME.

              If  you supply three arguments, the first must be a DATE and the
              second and third must be INTs.  The second and  third  arguments
              are interpreted as hours and minutes and converted to a TIME.

              If  you  supply  four  arguments,  the first three must be INTs,
              interpreted as the year, month and  day.   The  fourth  argument
              must be a TIME.

              Finally, if you supply five arguments, they must all be INTs and
              are interpreted as year, month, day, hour and minute.

       dawn([dq_date])
              Returns the time of "civil dawn" on the specified date.  If date
              is  omitted,  defaults to today().  If a datetime object is sup-
              plied, only the date component is used.

       day(dq_date)
              This function takes a DATE  or  DATETIME  as  an  argument,  and
              returns an INT that is the day-of-month component of date.

       daysinmon(i_m, i_y)
              Returns the number of days in month m (1-12) of the year y.

       defined(s_var)
              Returns 1 if the variable named by var is defined, or 0 if it is
              not.
              Note that defined() takes a STRING argument; thus, to  check  if
              variable X is defined, use:

                        defined("X")

              and not:

                        defined(X)

              The  second  example will attempt to evaluate X, and will return
              an error if it is undefined or not of type STRING.

       dosubst(s_str [,d_date [,t_time]]) or dosubst(s_str [,q_datetime])
              Returns a STRING that is the result of passing str  through  the
              substitution  filter described earlier.  The parameters date and
              time (or datetime) establish the effective trigger date and time
              used  by the substitution filter.  If date and time are omitted,
              they default to today() and now().

              Note that if str does not end with "%", a newline character will
              be added to the end of the result.  Also, calling dosubst() with
              a date that is in the past (i.e., if date < today())  will  pro-
              duce undefined results.

              Dosubst()  is  only  available starting from version 03.00.04 of
              Remind.

       dusk([dq_date])
              Returns the time of "civil twilight" on the specified date.   If
              date is omitted, defaults to today().

       easterdate(dqi_arg)
              If arg is an INT, then returns the date of Easter Sunday for the
              specified year.  If arg is a DATE or DATETIME, then returns  the
              date  of the next Easter Sunday on or after arg.  (The time com-
              ponent of a datetime is ignored.)

       evaltrig(s_trigger [,dq_start])
              Evaluates trigger as if it were a REM or IFTRIG trigger specifi-
              cation  and returns the trigger date as a DATE (or as a DATETIME
              if there is an AT clause.)  Returns a negative INT if no trigger
              could be computed.

              Normally,  evaltrig  finds a trigger date on or after today.  If
              you supply the start  argument,  then  it  scans  starting  from
              there.

              For example, the expression:

                evaltrig("Mon 1", '2008-10-07')

              returns '2008-11-03', since that is the first date on or after 7
              October 2008 that satisfies "Mon 1".

              If you want to see how many days it is from the first Monday  in
              October, 2008 to the first Monday in November, 2008, use:

                evaltrig("Mon 1", '2008-11-01') - evaltrig("Mon 1", '2008-10-01')

              and the answer is 28.  The trigger argument to evaltrig can have
              all the usual trigger clauses (OMIT, AT, SKIP, etc.) but  cannot
              have a SATISFY, MSG, etc. reminder-type clause.

       filedate(s_filename)
              Returns the modification date of filename.  If filename does not
              exist, or its modification date is  before  the  year  baseyr(),
              then 1 January of baseyr() is returned.

       filedatetime(s_filename)
              Returns the modification date and time of filename.  If filename
              does not exist, or its modification  date  is  before  the  year
              baseyr(), then midnight, 1 January of baseyr() is returned.

       filedir()
              Returns  the directory that contains the current file being pro-
              cessed.  It may be a relative or absolute pathname, but is guar-
              anteed to be correct for use in an INCLUDE command as follows:

                 INCLUDE [filedir()]/stuff

              This includes the file "stuff" in the same directory as the cur-
              rent file being processed.

       filename()
              Returns (as a STRING) the name of the current  file  being  pro-
              cessed  by  Remind.   Inside included files, returns the name of
              the included file.

       getenv(s_envvar)
              Similar to the getenv(2) system call.  Returns a  string  repre-
              senting   the  value  of  the  specified  environment  variable.
              Returns "" if the environment variable  is  not  defined.   Note
              that  the names of environment variables are generally case-sen-
              sitive; thus, getenv("HOME") is not the same as getenv("home").

       hebdate(i_day, s_hebmon [,idq_yrstart [,i_jahr [,i_aflag]]])
              Support for Hebrew dates - see the section "The Hebrew Calendar"

       hebday(dq_date)
              Support for Hebrew dates - see the section "The Hebrew Calendar"

       hebmon(dq_date)
              Support for Hebrew dates - see the section "The Hebrew Calendar"

       hebyear(dq_date)
              Support for Hebrew dates - see the section "The Hebrew Calendar"

       hour(tq_time)
              Returns the hour component of time.

       iif(si_test1, x_arg1, [si_test2, x_arg2,...], x_default)
              If test1 is not zero or the null string, returns  arg1.   Other-
              wise, if test2 is not zero or the null string, returns arg2, and
              so on.  If all of the test arguments are false, returns default.
              Note  that  all  arguments  are always evaluated.  This function
              accepts an odd number of arguments - note that prior to  version
              03.00.05  of  Remind, it accepted 3 arguments only.  The 3-argu-
              ment version of iif() is compatible with  previous  versions  of
              Remind.

       index(s_search, s_target [,i_start)
              Returns  an  INT  that  is  the location of target in the string
              search.  The first character of a string is numbered 1.  If tar-
              get does not exist in search, then 0 is returned.

              The optional parameter start specifies the position in search at
              which to start looking for target.

       isdst([d_date [,t_time]]) or isdst(q_datetime)
              Returns a positive number if daylight saving time is  in  effect
              on  the  specified  date and time.  Date defaults to today() and
              time defaults to midnight.

              Note that this function is only as reliable as  the  C  run-time
              library  functions.   It  is  available  starting  with  version
              03.00.07 of Remind.

       isleap(idq_arg)
              Returns 1 if arg is a leap year, and 0 otherwise.  Arg can be an
              INT,  DATE  or  DATETIME  object.  If a DATE or DATETIME is sup-
              plied, then the year component is used in the test.

       isomitted(dq_date)
              Returns 1 if date is omitted, given the current global OMIT con-
              text.   Returns  0  otherwise.  (If a datetime is supplied, only
              the date part is used.)  Note that any local  OMIT  or  OMITFUNC
              clauses are not taken into account by this function.

       language()
              Returns  a STRING naming the language supported by Remind.  (See
              "Foreign Language Support.") By default, Remind is  compiled  to
              support  English  messages,  so this function returns "English".
              For other languages, this function will return the English  name
              of  the  language  (e.g.  "German")  Note that language() is not
              available in versions of Remind prior to 03.00.02.

       lower(s_string)
              Returns a STRING with all upper-case characters in  string  con-
              verted to lower-case.

       max(x_arg1 [,x_arg2...)
              Can  take any number of arguments, and returns the maximum.  The
              arguments can be of any type, but must all be of the same  type.
              They are compared as with the > operator.

       min(x_arg1 [,x_arg2...)
              Can  take any number of arguments, and returns the minimum.  The
              arguments can be of any type, but must all be of the same  type.
              They are compared as with the < operator.

       minsfromutc([d_date [,t_time]]) or minsfromutc(q_datetime)
              Returns  the  number  of minutes from Universal Time Coordinated
              (formerly GMT) to local time on the  specified  date  and  time.
              Date  defaults  to  today()  and  time defaults to midnight.  If
              local time is before UTC, the result  is  negative.   Otherwise,
              the result is positive.

              Note  that  this  function is only as reliable as the C run-time
              library  functions.   It  is  available  starting  with  version
              03.00.07 of Remind.

       minute(tq_time)
              Returns the minute component of time.

       mon(dqi_arg)
              If  arg is of DATE or DATETIME type, returns a string that names
              the month component of the date.  If arg is an INT from 1 to 12,
              returns a string that names the month.

       monnum(dq_date)
              Returns an INT from 1 to 12, representing the month component of
              date.

       moondate(i_phase [,d_date [,t_time]]) or moondate(i_phase, q_datetime)
              This function returns the date of the first  occurrence  of  the
              phase  phase  of  the moon on or after date and time.  Phase can
              range from 0 to 3, with 0 signifying new moon, 1 first  quarter,
              2  full  moon,  and  3  third  quarter.   If date is omitted, it
              defaults to today().  If time is omitted, it  defaults  to  mid-
              night.

              For  example,  the  following  returns the date of the next full
              moon:

                        SET fullmoon moondate(2)

       moontime(i_phase [,d_date [,t_time]]) or moontime(i_phase, q_datetime)
              This function returns the time of the first  occurrence  of  the
              phase  phase  of  the moon on or after date and time.  Phase can
              range from 0 to 3, with 0 signifying new moon, 1 first  quarter,
              2  full  moon,  and  3  third  quarter.   If date is omitted, it
              defaults to today().  If time is omitted, it  defaults  to  mid-
              night.   Moontime()  is  intended to be used in conjunction with
              moondate().  The moondate() and moontime() functions  are  accu-
              rate to within a couple of minutes of the times in "Old Farmer's
              Almanac" for Ottawa, Ontario.

              For example, the following returns the date and time of the next
              full moon:

                        MSG Next full moon at [moontime(2)] on [moondate(2)]

       moondatetime(i_phase   [,d_date  [,t_time]])  or  moondatetime(i_phase,
       q_datetime)
              This function is similar to moondate and moontime, but returns a
              DATETIME result.

       moonphase([d_date [,t_time]]) or moonphase(q_datetime)
              This  function  returns  the phase of the moon on date and time,
              which  default  to  today()  and  midnight,  respectively.   The
              returned  value  is  an  integer from 0 to 359, representing the
              phase of the moon in degrees.  0 is a new moon, 180  is  a  full
              moon, 90 is first-quarter, etc.

       ndawn([dq_date])
              Returns  the  time of "nautical dawn" on the specified date.  If
              date is omitted, defaults to today().  If a datetime  object  is
              supplied, only the date component is used.

       ndusk([dq_date])
              Returns  the  time of "nautical twilight" on the specified date.
              If date is omitted, defaults to today().

       nonomitted(dq_start, dq_end [,s_wkday...])
              This function returns the number  of  non-omitted  days  between
              start  and  end.   If  start is non-omitted, then it is counted.
              end is never counted.

              Note that end must be greater than or equal to start or an error
              is  reported.  In addition to using the global OMIT context, you
              can supply additional arguments that are names of weekdays to be
              omitted.   However,  in a REM command, any local OMITFUNC clause
              is not taken into account by this function.

              For example, the following line sets a to 11 (assuming no global
              OMITs):

                   set a nonomitted('2007-08-01', '2007-08-16', "Sat", "Sun")

              because  Thursday,  16  August 2007 is the 11th working day (not
              counting Saturday and Sunday) after Wednesday, 1 August 2007.

              nonomitted has various uses.  For example, many schools run on a
              six-day cycle and the day number is not incremented on holidays.
              Suppose the school year starts with Day 1 on 4  September  2007.
              The following reminder will label day numbers in a calendar:

                 IF today() >= '2007-09-04'
                     set daynum nonomitted('2007-09-04', today(), "Sat", "Sun")
                     REM OMIT SAT SUN SKIP CAL Day [(daynum % 6) + 1]
                 ENDIF

              Obviously,  the  answer  you  get from nonomitted depends on the
              global OMIT context.  If you use moveable  OMITs,  you  may  get
              inconsistent results.

              Here  is  a more complex use for nonomitted.  My garbage collec-
              tion follows two interleaved 14-day cycles: One Friday,  garbage
              and  paper recycling ("Black Box") are collected.  The next Fri-
              day, garbage and plastic recycling ("Blue Box")  are  collected.
              If  any  of  Monday-Friday  is  a holiday, collection is delayed
              until the Saturday.  Here's a way to encode these rules:

                 fset _garbhol(x) wkdaynum(x) == 5 && nonomitted(x-4, x+1) < 5
                 REM 12 November 1999 *14 AFTER OMITFUNC _garbhol MSG Black Box
                 REM 19 November 1999 *14 AFTER OMITFUNC _garbhol MSG Blue Box

              Here's how it  works:   The  _garbhol(x)  user-defined  function
              returns  1  if and only if (1) x is a Friday and (2) there is at
              least one OMITted day from the previous Monday up to and includ-
              ing the Friday.

              The first REM statement sets up the 14-day black-box cycle.  The
              AFTER keyword makes it move collection to the Saturday if _garb-
              hol  returns  1.   The  second  REM statement sets up the 14-day
              blue-box cycle with a similar adjustment made by AFTER  in  con-
              junction with _garbhol.

       now()  Returns  the  current  system time, as a TIME type.  This may be
              the actual time, or a time supplied on the command line.

       ord(i_num)
              Returns a string that is the ordinal number num.   For  example,
              ord(2) returns "2nd", and ord(213) returns "213th".

       ostype()
              Returns "UNIX".  Remind used to run on OS/2 and MS-DOS, but does
              not any longer.

       plural(i_num [,s_str1 [,s_str2]])
              Can take from one to three arguments.  If one argument  is  sup-
              plied, returns "s" if num is not 1, and "" if num is 1.

              If  two arguments are supplied, returns str1 + "s" if num is not
              1.  Otherwise, returns str1.

              If three arguments are supplied, returns str1 if num is  1,  and
              str2 otherwise.

       psmoon(i_phase [,i_size [,s_note [,i_notesize]]])
              [DEPRECATED]  Returns  a STRING consisting of PostScript code to
              draw a moon in the upper-left hand corner of the  calendar  box.
              Phase  specifies  the  phase of the moon, and is 0 (new moon), 1
              (first quarter), 2 (full moon) or 3 (third quarter).  If size is
              specified,  it  controls  the  radius  of the moon in PostScript
              units (1/72 inch.)  If it is not specified or is  negative,  the
              size of the day-number font is used.

              For  example, the following four lines place moon symbols on the
              PostScript calendar:

                        REM [moondate(0)] PS [psmoon(0)]
                        REM [moondate(1)] PS [psmoon(1)]
                        REM [moondate(2)] PS [psmoon(2)]
                        REM [moondate(3)] PS [psmoon(3)]

              If note is specified, the text is used to annotate the moon dis-
              play.   The font is the same font used for calendar entries.  If
              notesize is given, it specifies the font size  to  use  for  the
              annotation, in PostScript units (1/72 inch.)  If notesize is not
              given, it defaults to the size used for calendar  entries.   (If
              you  annotate  the  display, be careful not to overwrite the day
              number -- Remind does not check for this.)  For example, if  you
              want  the time of each new moon displayed, you could use this in
              your reminder script:

                   REM [moondate(0)] PS [psmoon(0, -1, moontime(0)+"")]

              Note how the time is coerced to a string  by  concatenating  the
              null string.

       psshade(i_gray) or psshade(i_red, i_green, i_blue)
              [DEPRECATED]  Returns  a STRING that consists of PostScript com-
              mands to shade a calendar box.  Num can range from 0 (completely
              black) to 100 (completely white.)  If three arguments are given,
              they specify red, green  and  blue  intensity  from  0  to  100.
              Here's an example of how to use this:

                        REM Sat Sun PS [psshade(95)]

              The  above  command  emits  PostScript code to lightly shade the
              boxes for Saturday and Sunday in a PostScript calendar.

              Note that psmoon and psshade are deprecated; instead you  should
              use the SPECIAL SHADE and SPECIAL MOON reminders as described in
              "Out-of-Band Reminders."

       realcurrent()
              Returns (as a DATETIME) the true date and time of  day  as  pro-
              vided  by  the  operating  system.   This is in contrast to cur-
              rent(), which may return a time supplied on the command line.

       realnow()
              Returns the true time of day as provided by the  operating  sys-
              tem.  This is in contrast to now(), which may return a time sup-
              plied on the command line.

       realtoday()
              Returns the date as provided by the operating system.   This  is
              in contrast to Remind's concept of "today", which may be changed
              if it is running in calendar mode, or if a date  has  been  sup-
              plied on the command line.

       sgn(i_num)
              Returns  -1  if  num is negative, 1 if num is positive, and 0 if
              num is zero.

       shell(s_cmd [,i_maxlen])
              Executes cmd as a system command,  and  returns  the  first  511
              characters of output resulting from cmd.  Any whitespace charac-
              ter in the output is converted to a space.  Note that if RUN OFF
              has  been executed, or the -r command-line option has been used,
              shell() will result in an error, and cmd will not be executed.

              If maxlen is specified, then shell() returns  the  first  maxlen
              characters  of output (rather than the first 511).  If maxlen is
              specified as a negative number, then all the output from cmd  is
              returned.

       slide(d_start, i_amt [,s_wkday...])
              This  function  is  the inverse of nonomitted.  It adds amt days
              (which can be negative) to start,  not  counting  omitted  days.
              The  optional  wkday  arguments  are additional weekday names to
              omit.

              Consider this example:

                   OMIT 14 May 2009
                   SET a slide('2009-05-13', 5, "Sat", "Sun")

              In this case, a is set to 2009-05-21.  That's because  we  slide
              forward  by  5  days, not including Thursday, May 14 or Saturday
              and Sunday, May 16 and 17.  You can go backwards, too, so:

                   OMIT 14 May 2009
                   SET a slide('2009-05-21', -5, "Sat", "Sun")

              takes a back to 2009-05-13.

       strlen(s_str)
              Returns the length of str.

       substr(s_str, i_start [,i_end])
              Returns a STRING consisting of all characters in str from  start
              up  to  and  including end.  Characters are numbered from 1.  If
              end is not supplied, then it defaults to the length of str.

       sunrise([dq_date])
              Returns a TIME indicating the time of sunrise on  the  specified
              date (default today().)  In high latitudes, there may be no sun-
              rise on a particular day, in which case  sunrise()  returns  the
              INT 0 if the sun never sets, or 1440 if it never rises.

       sunset([dq_date])
              Returns  a  TIME  indicating the time of sunset on the specified
              date (default today().)  In high latitudes, there may be no sun-
              set  on a particular day, in which case sunset() returns the INT
              0 if the sun never rises, or 1440 if it never sets.

              The functions sunrise() and sunset() are based on  an  algorithm
              in  "Almanac  for Computers for the year 1978" by L. E. Doggett,
              Nautical Almanac Office, USNO.  They require  the  latitude  and
              longitude  to  be  specified  by  setting the appropriate system
              variables.  (See "System Variables".)  The sun functions  should
              be  accurate  to within about 4 minutes for latitudes lower than
              60 degrees.  The functions are available starting  from  version
              03.00.07 of Remind.

       time(i_hr, i_min)
              Creates  a TIME with the hour and minute components specified by
              hr and min.

       timepart(tq_datetime)
              Returns a TIME object representing the time portion of datetime.

       today()
              Returns Remind's notion of "today."  This may be the actual sys-
              tem date, or a date supplied on the command line, or the date of
              the calendar entry currently being computed.

       trigdate()
              Returns the calculated trigger date of the last  REM  or  IFTRIG
              command.   If  used  in  the body of a REM command, returns that
              command's trigger date.  If the most recent REM command did  not
              yield a computable trigger date, returns the integer 0.

       trigdatetime()
              Similar to trigdate(), but returns a DATETIME if the most recent
              triggerable REM command had an AT clause.  If there  was  no  AT
              clause,  returns  a  DATE.   If  no  trigger  could be computed,
              returns the integer 0.  See "MULTI-DAY EVENTS" for more informa-
              tion.

       trigeventstart()
              Returns  a  DATETIME  representing  the start of the most recent
              triggerable REM command that had an AT clause.  For events with-
              out  a  DURATION  or that do not span multiple days, returns the
              same as trigdatetime().  If the REM command did not have  an  AT
              clause,  returns the integer -1 (and differs from trigdatetime()
              in this respect.)  See "MULTI-DAY EVENTS" for more information.

       trigeventduration()
              Returns a TIME representing the  duration  of  the  most  recent
              triggerable  REM  command  that had an AT and a DURATION clause.
              If the event does not span multiple days, returns the same thing
              as  trigduration().  If the REM command lacked an AT or DURATION
              clause, returns -1.  See "MULTI-DAY EVENTS"  for  more  informa-
              tion.

       trigback()
              Returns  the  "back"  amount  of the last REM or IFTRIG command.
              Returns a positive integer N if the "back" is of the form -N, or
              a  negative  integer  if  it is of the form --N.  If there is no
              "back", then returns 0.

       trigdelta()
              Returns the "delta" amount of the last REM  or  IFTRIG  command.
              Returns  a  positive integer N if the "delta" is of the form +N,
              or a negative integer if it is of the form ++N.  If there is  no
              "delta", then returns 0.

       trigtimedelta()
              Similar  to  trigdelta(),  but  returns the delta used in the AT
              clause of a timed reminder.

       trigrep()
              Returns the "repeat" amount of the last REM or  IFTRIG  command.
              Returns  a positive integer N if the "repeat" is of the form *N.
              If there is no "repeat", then returns 0.

       trigtimerep()
              Similar to trigrep(), but returns the  repeat  used  in  the  AT
              clause of a timed reminder.

       trigduration()
              Returns  (as  a  TIME  type)  the  DURATION parameter of a timed
              reminder.  If there is no DURATION parameter, returns the  inte-
              ger -1.  See "MULTI-DAY EVENTS" for more information.

       trigpriority()
              Returns the PRIORITY of the last REM or IFTRIG command.

       triguntil()
              Returns  (as a DATE type) the UNTIL parameter of the last REM or
              IFTRIG command.  If there was no UNTIL  parameter,  returns  the
              integer  -1.   If  there  is  a  THROUGH parameter, that will be
              returned by triguntil() since  "THROUGH  yyyy-mm-dd"  is  simply
              syntactic sugar for "*1 UNTIL yyyy-mm-dd".

       trigscanfrom()
              Returns  (as a DATE type) the SCANFROM parameter of the last REM
              or IFTRIG command.  If there was no SCANFROM parameter,  returns
              the  integer  -1.   Note  that  FROM  and  SCANFROM  interact; a
              reminder that has a "FROM yyyy-mm-dd" parameter will act  as  if
              it has a SCANFROM parameter whose value is the maximum of "yyyy-
              mm-dd" and today.

       trigfrom()
              Returns (as a DATE type) the FROM parameter of the last  REM  or
              IFTRIG  command.   If  there  was no FROM parameter, returns the
              integer -1.


       trigger(d_date   [,t_time    [,i_utcflag]])    or    trigger(q_datetime
       [,i_utcflag])
              Returns a string suitable for use in a REM command or a SCANFROM
              or UNTIL clause, allowing you  to  calculate  trigger  dates  in
              advance.   Note  that in earlier versions of Remind, trigger was
              required to convert a date into something the REM command  could
              consume.   However,  in this version of Remind, you can omit it.
              Note that trigger() always returns its result in  English,  even
              for foreign-language versions of Remind.  This is to avoid prob-
              lems with certain C libraries that do not handle accented  char-
              acters properly.  Normally, the date and time are the local date
              and time; however, if utcflag is non-zero, the date and time are
              interpreted  as  UTC  times,  and  are  converted to local time.
              Examples:

                   trigger('1993/04/01')

              returns "1 April 1993",

                   trigger('1994/08/09', 12:33)

              returns "9 August 1994 AT 12:33", as does:

                   trigger('1994/08/09@12:33').

              Finally:

                   trigger('1994/12/01', 03:00, 1)

              returns "30 November 1994 AT 22:00" for EST, which  is  5  hours
              behind UTC.  The value for your time zone may differ.

       trigtime()
              Returns  the time of the last REM command with an AT clause.  If
              the last REM did not have an AT clause, returns the  integer  0.
              If  a REM command has an AT clause with a DURATION, then you can
              compute the end time as trigtime() + trigduration().

       trigvalid()
              Returns 1 if the value returned by trigdate() is valid  for  the
              most recent REM command, or 0 otherwise.  Sometimes REM commands
              cannot calculate a trigger date.  For example, the following REM
              command can never be triggered:

                 REM Mon OMIT Mon SKIP MSG Impossible!

       typeof(x_arg)
              Returns "STRING", "INT", "DATE", "TIME" or "DATETIME", depending
              on the type of arg.

       tzconvert(q_datetime, s_srczone [,s_dstzone])
              Converts datetime from the time zone named  by  srczone  to  the
              time  zone named by dstzone.  If dstzone is omitted, the default
              system time zone is used.  The return value is a DATETIME.  Time
              zone  names  are system-dependent; consult your operating system
              for legal values.  Here is an example:

           tzconvert('2007-07-08@01:14', "Canada/Eastern", "Canada/Pacific")

                 returns

           2007-07-07@22:14

       upper(s_string)
              Returns a STRING with all lower-case characters in  string  con-
              verted to upper-case.

       value(s_varname [,x_default])
              Returns  the  value  of  the  specified  variable.  For example,
              value("X"+"Y") returns the  value  of  variable  XY,  if  it  is
              defined.  If XY is not defined, an error results.

              However,  if you supply a second argument, it is returned if the
              varname is not defined.   The  expression  value("XY",  0)  will
              return  0  if  XY  is  not defined, and the value of XY if it is
              defined.

       version()
              Returns a string specifying the version of Remind.  For  version
              03.00.04, returns "03.00.04".  It is guaranteed that as new ver-
              sions of Remind are released, the value  returned  by  version()
              will strictly increase, according to the rules for string order-
              ing.

       weekno([dq_date, [i_wkstart, [i_daystart]]])
              Returns the week number of the year.  If no arguments  are  sup-
              plied,  returns  the  ISO  8601 week number for today().  If one
              argument date is supplied, then returns the ISO 8601 week number
              for that date.  If two arguments are supplied, then wkstart must
              range from 0 to 6, and represents the  first  day  of  the  week
              (with  0 being Sunday and 6 being Saturday.).  If wkstart is not
              supplied, then it defaults to 1.  If the third argument daystart
              is  supplied, then it specifies when Week 1 starts.  If daystart
              is less than or equal to 7, then Week  1  starts  on  the  first
              wkstart  on or after January daystart.  Otherwise, Week 1 starts
              on the first wkstart on or after December daystart.  If omitted,
              daystart defaults to 29 (following the ISO 8601 definition.)

       wkday(dqi_arg)
              If  arg is a DATE or DATETIME, returns a string representing the
              day of the week of the date.  If arg is an  INT  from  0  to  6,
              returns the corresponding weekday ("Sunday" to "Saturday").

       wkdaynum(dq_date)
              Returns a number from 0 to 6 representing the day-of-week of the
              specified date.  (0 represents Sunday, and 6  represents  Satur-
              day.)

       year(dq_date)
              Returns a INT that is the year component of date.


MULTI-DAY EVENTS
       If  you  specify a start time with AT and a duration with DURATION, you
       can create events that span multiple  days.   Consider  these  two  REM
       statements:

           REM 1991-02-13 AT 16:00 DURATION 72:00 MSG 72-hour event
           REM 1991-02-13 THROUGH 1991-02-16 AT 16:00 MSG Four events

       The  first  statement creates a single event that starts on 13 February
       1991 at 16:00 and runs through 16 February 1991 at 16:00

       The second statements creates four separate events that start at  16:00
       on 13, 14, 15 and 16 February 1991 and have indefinite duration.

       Remind handles multi-day events specially.  These are the rules:

       On  the  first day of a multi-day event, trigdatetime() will return the
       starting date and time of the event, and trigduration() will return the
       original DURATION.

       On each subsequent day of a multi-day event, trigdatetime() will return
       midnight on the day in question, and  trigduration()  will  return  the
       remaining duration.  Consider this example:

           #!/bin/sh
           remind - 12 feb 1991 '*6' <<'EOF'
           BANNER %
           REM 1991-02-13 AT 16:00 DURATION 72:00 SATISFY 1
           set a trigdatetime()
           set b trigduration()
           set c trigeventstart()
           set d trigeventduration()
           MSG now=[today()] dt=[a] dur=[b] estart=[c] edur=[d]%
           EOF

       The output is:

       now=1991-02-12 dt=1991-02-13@16:00 dur=72:00 estart=1991-02-13@16:00 edur=72:00
       now=1991-02-13 dt=1991-02-13@16:00 dur=72:00 estart=1991-02-13@16:00 edur=72:00
       now=1991-02-14 dt=1991-02-14@00:00 dur=64:00 estart=1991-02-13@16:00 edur=72:00
       now=1991-02-15 dt=1991-02-15@00:00 dur=40:00 estart=1991-02-13@16:00 edur=72:00
       now=1991-02-16 dt=1991-02-16@00:00 dur=16:00 estart=1991-02-13@16:00 edur=72:00
       now=1991-02-17 dt=1991-02-13@16:00 dur=72:00 estart=-1 edur=-1

       As  you see, the trigdatetime() and trigduration() functions return the
       start time and duration of the remaining portion of a multi-day  event,
       whereas trigeventstart and trigeventduration always return the original
       start and duration of the multi-day event.  Note also that  the  return
       value   for   expired   reminders   is  not  reliable;  the  fact  that
       trigeventstart and trigeventduration return  -1  in  that  case  is  an
       implementation artifact.

       SELF-OVERLAPPING EVENTS

       A  multi-day  event  has the possibility of "overlapping itself".  When
       this happens, Remind prefers the later event (only one copy of an event
       is ever triggered for a given date.)  Consider this example:

          #!/bin/sh
          remind - '*5' 10 Feb 1991 <<'EOF'

          BANNER %
          REM MON at 0:00 DURATION 192:0 MSG [today()] [trigeventstart()] [trigduration()]%

          EOF

       The output is:

          1991-02-10 1991-02-04@00:00 48:00
          1991-02-11 1991-02-11@00:00 192:00
          1991-02-12 1991-02-11@00:00 168:00
          1991-02-13 1991-02-11@00:00 144:00
          1991-02-14 1991-02-11@00:00 120:00

       Although  the  event  from  1991-02-04  still  has  24  hours  left  on
       1991-02-11, the fresh occurrence on 1991-02-11 takes precedences and is
       the one that is triggered.

       I do not recommend constructing self-overlapping multi-day events.

EXPRESSION PASTING
       An  extremely  powerful  feature  of Remind is its macro capability, or
       "expression pasting."

       In almost any situation where Remind is not  expecting  an  expression,
       you  can "paste" an expression in.  To do this, surround the expression
       with square brackets.  For example:

            REM [mydate] MSG foo

       This evaluates the expression "mydate", where  "mydate"  is  presumably
       some  pre-computed variable, and then "pastes" the result into the com-
       mand-line for the parser to process.

       A formal description of this is:  When Remind encounters a  "pasted-in"
       expression,  it  evaluates  the expression, and coerces the result to a
       STRING.  It then substitutes the string for the  pasted-in  expression,
       and  continues  parsing.  Note, however, that expressions are evaluated
       only once, not recursively.  Thus, writing:

            ["[a+b]"]

       causes Remind to read the token "[a+b]".  It does not interpret this as
       a  pasted-in  expression.  In fact, the only way to get a literal left-
       bracket into a reminder is to use ["["].

       You can use expression pasting almost anywhere.  However, there  are  a
       few exceptions:

       o      If  Remind is expecting an expression, as in the SET command, or
              the IF command, you should not  include  square  brackets.   For
              example, use:

                 SET a 4+5
       and not:
                 SET a [4+5]

       o      You cannot use expression pasting for the first token on a line.
              For example, the following will not work:

                 ["SET"] a 1

              This restriction is because Remind must be able to unambiguously
              determine  the  first  token of a line for the flow-control com-
              mands (to be discussed later.)

              In fact, if Remind cannot determine the first token on  a  line,
              it  assumes  that it is a REM command.  If expression-pasting is
              used, Remind assumes it is a REM command.  Thus,  the  following
              three commands are equivalent:

                        REM 12 Nov 1993 AT 13:05 MSG BOO!
                        12 Nov 1993 AT 13:05 MSG BOO!
                        [12] ["Nov " + 1993] AT [12:05+60] MSG BOO!

       o      You  cannot  use  expression-pasting to determine the type (MSG,
              CAL, etc.) of a REM command.  You can paste  expressions  before
              and  after  the MSG, etc. keywords, but cannot do something like
              this:

                 REM ["12 Nov 1993 AT 13:05 " + "MSG" + " BOO!"]

       COMMON PITFALLS IN EXPRESSION PASTING

       Remember, when pasting  in  expressions,  that  extra  spaces  are  not
       inserted.  Thus, something like:

            REM[expr]MSG[expr]

       will probably fail.

       If  you use an expression to calculate a delta or back, ensure that the
       result is a positive number.  Something like:

            REM +[mydelta] Nov 12 1993 MSG foo

       will fail if mydelta happens to be negative.

FLOW CONTROL COMMANDS
       Remind has commands that control the flow of a reminder  script.   Nor-
       mally,  reminder  scripts  are processed sequentially.  However, IF and
       related commands allow you to process  files  conditionally,  and  skip
       sections that you don't want interpreted.

       THE IF COMMAND

       The IF command has the following form:

            IF expr
                 t-command
                 t-command...
            ELSE
                 f-command
                 f-command...
            ENDIF

       Note  that the commands are shown indented for clarity.  Also, the ELSE
       portion can be omitted.  IF commands can be nested up to a small limit,
       probably around 8 or 16 levels of nesting, depending on your system.

       If the expr evaluates to a non-zero INT, or a non-null STRING, then the
       IF portion is considered true, and the  t-commands  are  executed.   If
       expr  evaluates  to zero or null, then the f-commands (if the ELSE por-
       tion is present) are executed.  If expr is not of type INT  or  STRING,
       then it is an error.

       Examples:

            IF defined("want_hols")
                 INCLUDE /usr/share/remind/holidays
            ENDIF

            IF today() > '1992/2/10'
                 set missed_ap "You missed it!"
            ELSE
                 set missed_ap "Still have time..."
            ENDIF

       THE IFTRIG COMMAND

       The IFTRIG command is similar to an IF command, except that it computes
       a trigger (as in the REM command), and evaluates to true  if  a  corre-
       sponding REM command would trigger.  Examples:

            IFTRIG 1 Nov
                 ; Executed on 1 Nov
            ELSE
                 ; Executed except on 1 Nov
            ENDIF

            IFTRIG 1 -1 OMIT Sat Sun +4
                 ; Executed on last working day of month,
                 ; and the 4 working days preceding it
            ELSE
                 ; Executed except on above days
            ENDIF

       Note  that  the  IFTRIG  command  computes a trigger date, which can be
       retrieved with the trigdate() function.  You can use all of the  normal
       trigger  components,  such as UNTIL, delta, etc. in the IFTRIG command.
       However, you cannot use a type specifier such as CAL, MSG  or  SATISFY;
       attempting to do so yields a parse error.

USER-DEFINED FUNCTIONS
       In addition to the built-in functions, Remind allows you to define your
       own functions.  The FSET command does this for you:

       FSET fname(args) expr

       Fname is the name of the function, and follows the convention for  nam-
       ing  variables.   Args is a comma-separated list of arguments, and expr
       is an expression.  Args can be empty, in which case you define a  func-
       tion taking no parameters.  Here are some examples:

            FSET double(x) 2*x
            FSET yeardiff(date1, date2) year(date1) - year(date2)
            FSET since(x) ord(year(trigdate())-x)

       The last function is useful in birthday reminders.  For example:

            REM 1 Nov +12 MSG Dean's [since(1984)] birthday is %b.

       Dean  was  born  in 1984.  The above example, on 1 November 1992, would
       print:

            Dean's 8th birthday is today.

       Notes:

       o      If you access a variable in expr that is  not  in  the  list  of
              arguments, the "global" value (if any) is used.

       o      Function  and parameter names are significant only to 12 charac-
              ters.

       o      The value() function always accesses the  "global"  value  of  a
              variable,  even  if  it  has  the same name as an argument.  For
              example:

                        fset func(x) value("x")
                        set x 1
                        set y func(5)

              The above sequence sets y to 1, which is the global value of x.

       o      User-defined functions may call other functions, including other
              user-defined   functions.   However,  recursive  calls  are  not
              allowed.

       o      User-defined functions are  not  syntax-checked  when  they  are
              defined; parsing occurs only when they are called.

       o      If a user-defined function has the same name as a built-in func-
              tion, it is ignored and the built-in function is used.  To  pre-
              vent  conflicts with future versions of Remind (which may define
              more built-in functions), you may wish to name all  user-defined
              functions beginning with an underscore.

PRECISE SCHEDULING
       The  WARN keyword allows precise control over advance warning in a more
       flexible manner than the delta mechanism.  It should be followed by the
       name of a user-defined function, warn_function.

       If  a warn_function is supplied, then it must take one argument of type
       INT.  Remind ignores any delta, and instead calls warn_function succes-
       sively with the arguments 1, 2, 3, ...

       Warn_function's return value n is interpreted as follows:

       o      If  n is positive, then the reminder is triggered exactly n days
              before its trigger date.

       o      If n is negative, then it is triggered n days before its trigger
              date, not counting OMITted days.

       As  an  example, suppose you wish to be warned of American Independence
       Day 5, 3, and 1 days in advance.  You could use this:

            FSET _wfun(x) choose(x, 5, 3, 1, 0)
            REM 4 July WARN _wfun MSG American Independence Day is %b.

       NOTES

       1      If an error occurs during the evaluation of warn_function,  then
              Remind  stops  calling  it and simply issues the reminder on its
              trigger date.

       2      If the absolute-values of the return values of warn_function are
              not monotonically decreasing, Remind stops calling it and issues
              the reminder on its trigger date.

       3      Warn_function should (as a matter of good style) return 0 as the
              final  value  in  its  sequence  of  return  values.  However, a
              reminder will always be triggered on its trigger  date,  regard-
              less of what warn_function does.

       Similarly  to  WARN,  the SCHED keyword allows precise control over the
       scheduling of timed reminders.  It should be followed by the name of  a
       user-defined function, sched_function.

       If a scheduling function is supplied, then it must take one argument of
       type INT.  Rather than using the AT time, time delta, and time  repeat,
       Remind  calls  the scheduling function to determine when to trigger the
       reminder.  The first time the reminder is queued, the scheduling  func-
       tion  is called with an argument of 1.  Each time the reminder is trig-
       gered, it is re-scheduled by calling the scheduling function again.  On
       each call, the argument is incremented by one.

       The  return  value of the scheduling function must be an INT or a TIME.
       If the return value is a TIME, then the reminder is re-queued to  trig-
       ger  at that time.  If it is a positive integer n, then the reminder is
       re-queued to trigger at the  previous  trigger  time  plus  n  minutes.
       Finally,  if it is a negative integer or zero, then the reminder is re-
       queued to trigger n minutes before the AT time.  Note that  there  must
       be an AT clause for the SCHED clause to do anything.

       Here's an example:

            FSET _sfun(x) choose(x, -60, 30, 15, 10, 3, 1, 1, 1, 1, 0)
            REM AT 13:00 SCHED _sfun MSG foo

       The reminder would first be triggered at 13:00-60 minutes, or at 12:00.
       It would next be triggered 30 minutes later, at 12:30.  Then, it  would
       be triggered at 12:45, 12:55, 12:58, 12:59, 13:00, 13:01 and 13:02.

       NOTES

       1      If  an  error  occurs  during the evaluation of sched_func, then
              Remind reverts to using the AT time and  the  delta  and  repeat
              values, and never calls sched_func again.

       2      If  processing sched_func yields a time earlier than the current
              system time, it is repeatedly called  with  increasing  argument
              until  it  yields  a  value greater than or equal to the current
              time.  However, if the sequence of values calculated during  the
              repetition  is  not  strictly increasing, then Remind reverts to
              the default behaviour and never calls sched_func again.

       3      It is quite possible  using  sched_func  to  keep  triggering  a
              reminder even after the AT-time.  However, it is not possible to
              reschedule a reminder past midnight - no crossing of date bound-
              aries  is  allowed.  Also, it is quite possible to not trigger a
              reminder on the AT time when  you  use  a  scheduling  function.
              However,  if your scheduling function is terminated (for reasons
              1 and 2) before the AT time of the reminder, it  will  be  trig-
              gered at the AT time, because normal processing takes over.

       4      Your  scheduling  functions  should  (as a matter of good style)
              return 0 when no more scheduling is required.  See the example.

       5      All scheduling functions are evaluated after the  entire  Remind
              script  has  been read in.  So whatever function definitions are
              in effect at the end of the script are used.

THE SATISFY CLAUSE
       The form of REM that uses SATISFY is as follows:

       REM trigger SATISFY expr

       The way this works is as follows:  Remind first  calculates  a  trigger
       date,  in  the  normal fashion.  Next, it sets trigdate() to the calcu-
       lated trigger date.  It then evaluates expr.  If the result is not  the
       null  string  or zero, processing ends.  Otherwise, Remind computes the
       next trigger date, and re-tests expr.  This iteration  continues  until
       expr  evaluates  to  non-zero or non-null, or until the iteration limit
       specified with the -x command-line option is reached.

       If expr is not satisfied, then trigvalid() is set to 0  and  the  error
       message  "Can't  compute trigger" is issued.  Otherwise, trigvalid() is
       set to 1.

       This is really useful only if expr involves a call to the trigdate() or
       related functions; otherwise, expr will not change as Remind iterates.

       An example of the usefulness of SATISFY:  Suppose you wish to be warned
       of every Friday the 13th.  Your first attempt may be:

            # WRONG!
            REM Fri 13 +2 MSG Friday the 13th is %b.

       But this won't work.  This reminder triggers on the first Friday on  or
       after  the 13th of each month.  The way to do it is with a more compli-
       cated sequence:

            REM 13 SATISFY wkdaynum(trigdate()) == 5
            IF trigvalid()
                 REM [trigdate()] +2 MSG \
                 Friday the 13th is %b.
            ENDIF

       You can write the REM statement a little more concisely:

            REM 13 SATISFY $Tw == 5

       Let's see how this works.  The SATISFY clause iterates through all  the
       13ths of successive months, until a trigger date is found whose day-of-
       week is Friday (== 5).  If a valid date was found, we  use  the  calcu-
       lated trigger date to set up the next reminder.

       We could also have written:

            REM Fri SATISFY day(trigdate()) == 13

       but  this  would  result in more iterations, since "Fridays" occur more
       often than "13ths of the month."

       This technique of using one REM command to calculate a trigger date  to
       be used by another command is quite powerful.  For example, suppose you
       wanted to OMIT Labour day, which is the first Monday in September.  You
       could use:

            # Note: SATISFY 1 is an idiom for "do nothing"
            REM Mon 1 Sept SATISFY 1
            OMIT [trigdate()]

       CAVEAT: This only omits the next Labour Day, not all Labour Days in the
       future.  This could cause strange results,  as  the  OMIT  context  can
       change depending on the current date.  For example, if you use the fol-
       lowing command after the above commands:

            REM Mon AFTER msg hello

       the result will not be as you expect.  Consider  producing  a  calendar
       for  September,  1992.   Labour  Day  was on Monday, 7 September, 1992.
       However, when Remind gets around to calculating the trigger  for  Tues-
       day,  8  September,  1992, the OMIT command will now be omitting Labour
       Day for 1993, and the "Mon AFTER" command will not be triggered.   (But
       see  the  description of SCANFROM in the section "Details about Trigger
       Computation.")

       It is probably best to stay away  from  computing  OMIT  trigger  dates
       unless you keep these pitfalls in mind.

       For  versions  of Remind starting from 03.00.07, you can include a MSG,
       RUN, etc. clause in a SATISFY clause as follows:

            REM trigger_stuff SATISFY [expr] MSG body

       Note that for this case only, the expr after SATISFY must  be  enclosed
       in square brackets.  It must come after all the other components of the
       trigger, and immediately before the MSG, RUN, etc.  keyword.   If  expr
       cannot be satisfied, then the reminder is not triggered.

       Thus, the "Friday the 13th" example can be expressed more compactly as:

            REM 13 +2 SATISFY [$Tw == 5] MSG Friday the 13th is %b.

       And  you  can  trigger  a reminder on Mondays, Wednesdays and Thursdays
       occurring on odd-numbered days of the month with the following:

            REM Mon Wed Thu SATISFY [$Td %2 ] MSG Here it is!!!

       Note that SATISFY and OMITFUNC can often be  used  to  solve  the  same
       problem,  though in different ways.  Sometimes a SATISFY is cleaner and
       sometimes an OMITFUNC; experiment and use whichever seems clearer.

DEBUGGING REMINDER SCRIPTS
       Although the command-line -d option is  useful  for  debugging,  it  is
       often  overkill.   For  example,  if  you  turn on the -dx option for a
       reminder file with many complex expressions, you'll get a  huge  amount
       of output.  The DEBUG command allows you to control the debugging flags
       under program control.  The format is:

       DEBUG [+flagson] [-flagsoff]

       Flagson and flagsoff consist of strings of the characters "extvlf" that
       correspond  to  the  debugging  options  discussed  in the command-line
       options section.  If preceded with a "+", the  corresponding  group  of
       debugging  options  is  switched on.  Otherwise, they are switched off.
       For example, you could use this sequence to debug a complicated expres-
       sion:

            DEBUG +x
            set a very_complex_expression(many_args)
            DEBUG -x

       THE DUMPVARS COMMAND

       The  command  DUMPVARS displays the values of variables in memory.  Its
       format is:

       DUMPVARS [var...]

       If you supply a space-separated list of variable names, the correspond-
       ing variables are displayed.  If you do not supply a list of variables,
       then all variables in memory are displayed.  To dump a system variable,
       put  its name in the list of variables to dump.  If you put a lone dol-
       lar sign in the list of variables to dump, then  all  system  variables
       will be dumped.

       THE ERRMSG COMMAND

       The ERRMSG command has the following format:

       ERRMSG body

       The  body  is  passed through the substitution filter (with an implicit
       trigger date of today()) and printed to the error output stream.  Exam-
       ple:

            IF !defined("critical_var")
                 ERRMSG You must supply a value for "critical_var"
                 EXIT
            ENDIF

       THE EXIT COMMAND

       The  above example also shows the use of the EXIT command.  This causes
       an  unconditional  exit  from  script  processing.   Any  queued  timed
       reminders are discarded.  If you are in calendar mode (described next),
       then the calendar processing is aborted.

       If you supply an INT-type expression after  the  EXIT  command,  it  is
       returned to the calling program as the exit status.  Otherwise, an exit
       status of 99 is returned.

       THE FLUSH COMMAND

       This command simply consists of the word FLUSH on  a  line  by  itself.
       The command flushes the standard output and standard error streams used
       by Remind.  This is not terribly useful to most people, but may be use-
       ful  if  you run Remind as a subprocess of another program, and want to
       use pipes for communication.

CALENDAR MODE
       If you supply the -c, -s or -p command-line option, then Remind runs in
       "calendar  mode."   In  this mode, Remind interprets the script repeat-
       edly, performing one iteration through the whole file for each  day  in
       the  calendar.   Reminders  that trigger are saved in internal buffers,
       and then inserted into the calendar in the appropriate places.

       If you also supply the -a option, then Remind will  not  include  timed
       reminders in the calendar.

       The -p option is used in conjunction with the Rem2PS program to produce
       a calendar in PostScript format.  For example,  the  following  command
       will send PostScript code to standard output:

            remind -p .reminders | rem2ps

       You can print a PostScript calendar by piping this to the lpr command.

       If you have a reminder script called ".reminders", and you execute this
       command:

            remind -c .reminders jan 1993

       then Remind executes the script 31 times, once for each day in January.
       Each  time  it executes the script, it increments the value of today().
       Any reminders whose trigger date matches today() are entered  into  the
       calendar.

       MSG and CAL-type reminders, by default, have their entire body inserted
       into the calendar.  RUN-type reminders are not normally  inserted  into
       the  calendar.   However,  if  you enclose a portion of the body in the
       %"...%" sequence, only that portion is inserted.  For example, consider
       the following:

            REM 6 Jan MSG %"Dianne's birthday%" is %b

       In  the normal mode, Remind would print "Dianne's birthday is today" on
       6 January.  However, in the calendar  mode,  only  the  text  "Dianne's
       birthday" is inserted into the box for 6 January.

       If you explicitly use the %"...%" sequence in a RUN-type reminder, then
       the text between the delimiters is inserted into the calendar.  If  you
       use  the  sequence %"%" in a MSG or CAL-type reminder, then no calendar
       entry is produced for that reminder.

       PRESERVING VARIABLES

       Because Remind iterates through the script for each day in  the  calen-
       dar,  slow operations may severely reduce the speed of producing a cal-
       endar.

       For example, suppose you set the variables "me" and "hostname" as  fol-
       lows:

            SET me shell("whoami")
            SET hostname shell("hostname")

       Normally,  Remind  clears  all variables between iterations in calendar
       mode.  However, if certain variables are slow to compute, and will  not
       change  between  iterations,  you  can "preserve" their values with the
       PRESERVE command.   Also,  since  function  definitions  are  preserved
       between  calendar iterations, there is no need to redefine them on each
       iteration.  Thus, you could use the following sequence:

            IF ! defined("initialized")
                 set initialized 1
                 set me shell("whoami")
                 set hostname shell("hostname")
                 fset func(x) complex_expr
                 preserve initialized me hostname
            ENDIF

       The operation is as  follows:   On  the  first  iteration  through  the
       script,  "initialized"  is  not defined.  Thus, the commands between IF
       and ENDIF are executed.  The PRESERVE command ensures that  the  values
       of  initialized,  me  and  hostname are preserved for subsequent itera-
       tions.  On the next iteration, the commands are skipped, since initial-
       ized has remained defined.  Thus, time-consuming operations that do not
       depend on the value of today() are done only once.

       Most system variables (those whose names start with '$') are  automati-
       cally preserved between calendar iterations.

       Note  that  for  efficiency, Remind caches the reminder script (and any
       INCLUDEd files) in memory when producing a calendar.

       Timed reminders are sorted and placed into the calendar in time  order.
       These are followed by non-timed reminders.  Remind automatically places
       the time of timed reminders in the calendar according to  the  -b  com-
       mand-line  option.   Reminders in calendar mode are sorted as if the -g
       option had been used; you can change the sort order in calendar mode by
       explicitly  using  the  -g option to specify a different order from the
       default.

       REPEATED EXECUTION

       If you supply a repeat parameter on the command line, and  do  not  use
       the  -c, -p, or -s options, Remind operates in a similar manner to cal-
       endar mode.  It repeatedly executes the reminder  script,  incrementing
       today() with each iteration.  The same rules about preserving variables
       and function definitions apply.  Note that using repeat on the  command
       line  also  enables  the  -q  option and disables any -z option.  As an
       example, if you want to see how Remind will behave for the  next  week,
       you can type:

            remind .reminders '*7'

       If you want to print the dates of the next 1000 days, use:

            (echo 'banner %'; echo 'msg [today()]%') | remind - '*1000'

INITIALIZING VARIABLES ON THE COMMAND LINE
       The  -i  option  is  used to initialize variables on the Remind command
       line.  The format is -ivar=expr, where expr is  any  valid  expression.
       Note  that  you  may have to use quotes or escapes to prevent the shell
       from interpreting special characters in expr.  You can have as many  -i
       options  as  you  want  on  the command line, and they are processed in
       order.  Thus, if a variable is defined in one  -i  option,  it  can  be
       referred to by subsequent -i options.

       Note  that  if  you supply a date on the command line, it is not parsed
       until all options have been processed.  Thus, if you use today() in any
       of the -i expressions, it will return the same value as realtoday() and
       not the date supplied on the command line.

       Any variables defined on the command line are  preserved  as  with  the
       PRESERVE command.

       You  should  not  have  any  spaces between the -i option and the equal
       sign; otherwise, strange variable names are created that  can  only  be
       accessed with the value() or defined() functions.

       You can also define a function on the command line by using:

       -ifunc(args)=definition

       Be sure to protect special characters from shell interpretation.

MORE ABOUT POSTSCRIPT
       The  PS  and  PSFILE  reminders  pass  PostScript  code directly to the
       printer.  They differ in that the  PS-type  reminder  passes  its  body
       directly to the PostScript output (after processing by the substitution
       filter) while the PSFILE-type's body should simply consist of  a  file-
       name.   The  Rem2PS program will open the file named in the PSFILE-type
       reminder, and include its contents in the PostScript output.

       The PostScript-type reminders for a particular day are included in  the
       PostScript  output in sorted order of priority.  Note that the order of
       PostScript commands has a major impact on the appearance of the  calen-
       dars.  For example, PostScript code to shade a calendar box will oblit-
       erate code to draw a moon symbol if the moon symbol code is  placed  in
       the  calendar  first.   For  this  reason, you should not provide PS or
       PSFILE-type reminders with priorities; instead, you should ensure  that
       they  appear  in  the reminder script in the correct order.  PostScript
       code should draw objects working from the background to the foreground,
       so  that  foreground  objects properly overlay background ones.  If you
       prioritize these reminders and run the  script  using  descending  sort
       order for priorities, the PostScript output will not work.

       All of the PostScript code for a particular date is enclosed in a save-
       restore pair.  However, if several PostScript-type reminders are  trig-
       gered for a single day, each section of PostScript is not enclosed in a
       save-restore pair - instead, the entire body of included PostScript  is
       enclosed.

       PostScript-type reminders are executed by the PostScript printer before
       any regular calendar entries.   Thus,  regular  calendar  entries  will
       overlay the PostScript-type reminders, allowing you to create shaded or
       graphical backgrounds for particular days.

       Before executing your PostScript code, the  origin  of  the  PostScript
       coordinate  system  is positioned to the bottom left-hand corner of the
       "box" in the calendar representing today().  This location  is  exactly
       in  the  middle  of the intersection of the bottom and left black lines
       delineating the box - you may have to  account  for  the  thickness  of
       these lines when calculating positions.

       Several  PostScript  variables are available to the PostScript code you
       supply.  All distance and size variables are in PostScript units  (1/72
       inch.)  The variables are:

       LineWidth
              The width of the black grid lines making up the calendar.

       Border The  border  between  the center of the grid lines and the space
              used to print calendar entries.  This border is  normally  blank
              space.

       BoxWidth and BoxHeight
              The  width and height of the calendar box, from center-to-center
              of the black gridlines.

       InBoxHeight
              The height from the center of the bottom black gridline  to  the
              top  of the regular calendar entry area.  The space from here to
              the top of the box is used only to draw the day number.

       /DayFont, /EntryFont, /SmallFont, /TitleFont and /HeadFont
              The fonts used to draw the day numbers,  the  calendar  entries,
              the  small  calendars,  the calendar title (month, year) and the
              day-of-the-week headings, respectively.

       DaySize, EntrySize, TitleSize and HeadSize
              The sizes of the above fonts.  (The size of the  small  calendar
              font  is not defined here.)  For example, if you wanted to print
              the Hebrew date next to the regular day number in the  calendar,
              use:

            REM PS Border BoxHeight Border sub DaySize sub moveto \
               /DayFont findfont DaySize scalefont setfont \
               ([hebday(today())] [hebmon(today())]) show

              Note how /DayFont and DaySize are used.

       Note  that  if  you  supply  PostScript code, it is possible to produce
       invalid PostScript files.  Always test your PostScript thoroughly  with
       a  PostScript  viewer before sending it to the printer.  You should not
       use any document structuring comments in your PostScript code.

DAEMON MODE
       If you use the -z command-line option,  Remind  runs  in  the  "daemon"
       mode.   In  this mode, no "normal" reminders are issued.  Instead, only
       timed reminders are collected and queued, and are then issued  whenever
       they reach their trigger time.

       In  addition,  Remind wakes up every few minutes to check the modifica-
       tion date on the reminder script (the filename supplied on the  command
       line.)   If  Remind detects that the script has changed, it re-executes
       itself in daemon mode, and interprets the changed script.

       In daemon mode, Remind also re-reads the remind script when it  detects
       that the system date has changed.

       In  daemon  mode,  Remind acts as if the -f option had been used, so to
       run in the daemon mode in the background, use:

            remind -z .reminders &

       If you use sh or bash, you may have  to  use  the  "nohup"  command  to
       ensure that the daemon is not killed when you log out.


PURGE MODE
       If  you  supply  the -j command-line option, Remind runs in purge mode.
       In this mode, it tries to purge expired reminders  from  your  reminder
       files.

       In  purge  mode, Remind reads your reminder file and creates a new file
       by appending ".purged" to the original file  name.   Note  that  Remind
       never edits your original file; it always creates a new .purged file.

       If  you  invoke  Remind  against  a directory instead of a file, then a
       .purged file is created for each *.rem file in the directory.

       Normally, Remind does not create  .purged  files  for  INCLUDed  files.
       However,  if  you  supply a numeric argument after -j, then Remind will
       create .purged files for the specified level of INCLUDE.  For  example,
       if  you invoke Remind with the argument -j2, then .purged files will be
       created for the file (or directory) specified on the command line,  any
       files  included  by  them, and any files included by those files.  How-
       ever, .purged files will  not  be  created  for  third-or-higher  level
       INCLUDE files.

       Determining  which  reminders have expired is extremely tricky.  Remind
       does its best, but you should always compare the .purged  file  to  the
       original file and hand-merge the changes back in.

       Remind annotates the .purged file as follows:

       An expired reminder is prefixed with:  #!P: Expired:

       In situations where Remind cannot reliably determine that something was
       expired, you may see the following comments inserted before  the  prob-
       lematic line:

          #!P: Cannot purge SATISFY-type reminders

          #!P: The next IF evaluated false...
          #!P: REM statements in IF block not checked for purging.

          #!P: The previous IF evaluated true.
          #!P: REM statements in ELSE block not checked for purging

          #!P: The next IFTRIG did not trigger.
          #!P: REM statements in IFTRIG block not checked for purging.

          #!P: Next line has expired, but contains expression...  please verify

          #!P: Next line may have expired, but contains non-constant expression

          #!P! Could not parse next line: Some-Error-Message-Here

       Remind  always annotates .purged files with lines beginning with "#!P".
       If such lines are encountered in the original file, they are not copied
       to the .purged file.

SORTING REMINDERS
       The -g option causes Remind to sort reminders by trigger date, time and
       priority before issuing them.  Note that reminders are still calculated
       in  the  order  encountered  in the script.  However, rather than being
       issued immediately, they are saved in an internal buffer.  When  Remind
       has  finished  processing  the script, it issues the saved reminders in
       sorted order.  The -g option can be followed by up to  four  characters
       that  must  all  be "a" or "d".  The first character specifies the sort
       order by trigger date (ascending or descending), the  second  specifies
       the  sort  order by trigger time and the third specifies the sort order
       by priority.  If the fourth character is "d", the untimed reminders are
       sorted  before  timed  reminders.  The default is to sort all fields in
       ascending order and to sort untimed reminders after timed reminders.

       In ascending order, reminders are issued with the most imminent  first.
       Descending  order is the reverse.  Reminders are always sorted by trig-
       ger date, and reminders with the same trigger date are then  sorted  by
       trigger  time.   If two reminders have the same date and time, then the
       priority is used to break ties.  Reminders with the same date, time and
       priority are issued in the order they were encountered.

       You can define a user-defined function called SORTBANNER that takes one
       DATE-type argument.  In sort mode, the following sequence happens:

       If Remind notices that the next reminder to issue has a different trig-
       ger  date  from  the  previous  one  (or  if  it is the first one to be
       issued), then SORTBANNER is called with the trigger date as  its  argu-
       ment.   The  result is coerced to a string, and passed through the sub-
       stitution filter with the appropriate trigger date.  The result is then
       displayed.

       Here's an example - consider the following fragment:

            # Switch off the normal banner
            BANNER %
            REM 11 March 1993 ++1 MSG Not so important
            REM 17 March 1993 ++7 MSG Way in the future
            REM 10 March 1993 MSG Important Reminder
            REM 11 March 1993 ++1 MSG Not so important - B
            FSET sortbanner(x) iif(x == today(), \
                 "***** THINGS TO DO TODAY *****", \
                 "----- Things to do %b -----")

       Running this with the -gaa option on 10 March 1993 produces the follow-
       ing output:

            ***** THINGS TO DO TODAY *****

            Important Reminder

            ----- Things to do tomorrow -----

            Not so important

            Not so important - B

            ----- Things to do in 7 days' time -----

            Way in the future

       You can use the args() built-in function to determine  whether  or  not
       SORTBANNER has been defined.  (This could be used, for example, to pro-
       vide a default definition for SORTBANNER in a system-wide file included
       at the end of the user's file.)  Here's an example:

            # Create a default sortbanner function if it hasn't already
            # been defined
            if args("sortbanner") != 1
                 fset sortbanner(x) "--- Things to do %b ---"
            endif

MSGPREFIX() AND MSGSUFFIX()
       You can define two functions in your script called msgprefix() and msg-
       suffix().  They should each accept one argument, a  number  from  0  to
       9999.

       In normal mode, for MSG- and MSF-type reminders, the following sequence
       occurs when Remind triggers a reminder:

       o      If msgprefix() is defined, it is evaluated with the priority  of
              the reminder as its argument.  The result is printed.  It is not
              passed through the substitution filter.

       o      The body of the reminder is printed.

       o      If msgsuffix() is defined, it is evaluated with the priority  of
              the reminder as its argument.  The result is printed.  It is not
              passed through the substitution filter.

       Here's  an  example:   The  following  definition   causes   priority-0
       reminders to be preceded by "URGENT", and priority-6000 reminders to be
       preceded by "(not important)".

            fset msgprefix(x) iif(x==0, "URGENT: ", \
                 x==6000, "(not important) ", "")

       In Calendar Mode (with the -c, -s or -p options), an analogous pair  of
       functions  named calprefix() and calsuffix() can be defined.  They work
       with all reminders that produce an entry in the  calendar  (i.e.,  CAL-
       and possibly RUN-type reminders as well as MSG-type reminders.)

       NOTES

       Normally,  the  body  of  a  reminder is followed by a carriage return.
       Thus, the results of msgsuffix() will appear on the next line.  If  you
       don't  want  this, end the body of the reminder with a percentage sign,
       "%".  If you want a space between your reminders, simply include a car-
       riage return (char(13)) as part of the msgsuffix() return value.

       If  Remind has problems evaluating msgprefix(), msgsuffix() or sortban-
       ner(), you will see a lot of error messages.  For an example  of  this,
       define the following:

            fset msgprefix(x) x/0

FOREIGN LANGUAGE SUPPORT
       Your  version  of  Remind  may have been compiled to support a language
       other than English.  This support may or may  not  be  complete  -  for
       example,  all  error  and usage messages may still be in English.  How-
       ever, at a minimum, foreign-language versions  of  Remind  will  output
       names  of  months and weekdays in the foreign language.  Also, the sub-
       stitution mechanism will substitute constructs suitable for the foreign
       language rather than for English.

       A  foreign-language version of Remind will accept either the English or
       foreign-language names of weekdays and months  in  a  reminder  script.
       However,  for  compatibility between versions of Remind, you should use
       only the English names in your scripts.  Also, if your  C  compiler  or
       run-time  libraries  are not "8-bit clean" or don't understand the ISO-
       Latin character set, month or day names with accented letters  may  not
       be recognized.

THE HEBREW CALENDAR
       Remind  has support for the Hebrew calendar, which is a luni-solar cal-
       endar.  This allows  you  to  create  reminders  for  Jewish  holidays,
       jahrzeits (anniversaries of deaths) and smachot (joyous occasions.)

       THE HEBREW YEAR

       The  Hebrew  year  has 12 months, alternately 30 and 29 days long.  The
       months are: Tishrey, Heshvan, Kislev, Tevet, Shvat, Adar, Nisan,  Iyar,
       Sivan,  Tamuz,  Av  and  Elul.   In Biblical times, the year started in
       Nisan, but Rosh Hashana (Jewish New Year) is now celebrated on the  1st
       and 2nd of Tishrey.

       In  a  cycle  of 19 years, there are 7 leap years, being years 3, 6, 8,
       11, 14, 17 and 19 of the cycle.  In a leap year, an extra month  of  30
       days is added before Adar.  The two Adars are called Adar A and Adar B.

       For  certain  religious  reasons,  the  year  cannot start on a Sunday,
       Wednesday or Friday.  To adjust for this, a day is taken off Kislev  or
       added  to Heshvan.  Thus, a regular year can have from 353 to 355 days,
       and a leap year from 383 to 385.

       When Kislev or Heshvan is short, it is called chaser, or lacking.  When
       it is long, it is called shalem, or full.

       The  Jewish  date  changes  at sunset.  However, Remind will change the
       date at midnight, not sunset.  So in the period between sunset and mid-
       night,  Remind  will  be a day earlier than the true Jewish date.  This
       should not be much of a problem in practice.

       The computations for the Jewish calendar  were  based  on  the  program
       "hdate"  written  by Amos Shapir of the Hebrew University of Jerusalem,
       Israel.  He also supplied the preceding explanation of the calendar.

       HEBREW DATE FUNCTIONS

       hebday(d_date)
              Returns the day of the Hebrew month corresponding  to  the  date
              parameter.   For  example, 12 April 1993 corresponds to 21 Nisan
              5753.  Thus, hebday('1993/04/12') returns 21.

       hebmon(d_date)
              Returns the name of the Hebrew month corresponding to date.  For
              example, hebmon('1993/04/12') returns "Nisan".

       hebyear(d_date)
              Returns  the  Hebrew  year  corresponding to date.  For example,
              hebyear('1993/04/12') returns 5753.

       hebdate(i_day, s_hebmon [,id_yrstart [,i_jahr [,i_aflag]]])
              The hebdate() function is the most complex of the Hebrew support
              functions.   It  can  take  from 2 to 5 arguments.  It returns a
              DATE corresponding to the Hebrew date.

              The day parameter can range from 1 to 30, and specifies the  day
              of the Hebrew month.  The hebmon parameter is a string that must
              name one of the Hebrew months specified above.   Note  that  the
              month must be spelled out in full, and use the English translit-
              eration shown previously.  You can also  specify  "Adar  A"  and
              "Adar B."  Month names are not case-sensitive.

              The  yrstart parameter can either be a DATE or an INT.  If it is
              a DATE, then the hebdate() scans for the first Hebrew date on or
              after that date.  For example:

                        hebdate(15, "Nisan", '1990/01/01')

              returns  1990/03/30,  because that is the first occurrence of 15
              Nisan on or after 1 January 1990.

              If yrstart is an INT, it is interpreted as a Hebrew year.  Thus:

                        hebdate(22, "Kislev", 5756)

              returns 1995/12/15, because that date corresponds to 22  Kislev,
              5756.   Note  that  none  of the Hebrew date functions will work
              with dates outside Remind's normal range for dates.

              If yrstart is not supplied, it defaults to today().

              The jahr modifies the behaviour of hebdate() as follows:

              If jahr is 0 (the default), then hebdate() keeps scanning  until
              it  finds  a  date  that exactly satisfies the other parameters.
              For example:

                        hebdate(30, "Adar A", 1993/01/01)

              returns 1995/03/02, corresponding to 30 Adar  A,  5755,  because
              that  is the next occurrence of 30 Adar A after 1 January, 1993.
              This behaviour  is  appropriate  for  Purim  Katan,  which  only
              appears in leap years.

              If jahr is 1, then the date is modified as follows:

              o      30 Heshvan is converted to 1 Kislev in years when Heshvan
                     is chaser

              o      30 Kislev is converted to 1 Tevet in years when Kislev is
                     chaser

              o      30 Adar A is converted to 1 Nisan in non-leapyears

              o      Other  dates in Adar A are moved to the corresponding day
                     in Adar in non-leapyears

              This behaviour is appropriate for smachot (joyous occasions) and
              for some jahrzeits - see "JAHRZEITS."

              if jahr is 2, then the date is modified as follows:

              o      30  Kislev  and 30 Heshvan are converted to 29 Kislev and
                     29 Heshvan, respectively, if the month is chaser

              o      30 Adar A is converted to 30 Shvat in non-leapyears

              o      Other dates in Adar A are moved to the corresponding  day
                     in Adar in non-leapyears

              if  jahr  is not 0, 1, or 2, it is interpreted as a Hebrew year,
              and the behaviour is calculated as described in  the  next  sec-
              tion, "JAHRZEITS."

              The  aflag  parameter modifies the behaviour of the function for
              dates in Adar during leap years.  The  aflag  is  only  used  if
              yrstart is a DATE type.

              The  aflag only affects date calculations if hebmon is specified
              as "Adar".  In leap years, the following algorithm is followed:

              o      If aflag is 0, then the date  is  triggered  in  Adar  B.
                     This is the default.

              o      If  aflag  is  1,  then  the date is triggered in Adar A.
                     This may be appropriate for jahrzeits  in  the  Ashkenazi
                     tradition; consult a rabbi.

              o      If  aflag is 2, then the date is triggered in both Adar A
                     and Adar B of  a  leap  year.   Some  Ashkenazim  perform
                     jahrzeit in both Adar A and Adar B.

       JAHRZEITS

       A  jahrzeit  is a yearly commemoration of someone's death.  It normally
       takes place on the anniversary of the death,  but  may  be  delayed  if
       burial is delayed - consult a rabbi for more information.

       In addition, because some months change length, it is not obvious which
       day the anniversary of a death is.  The following rules are used:

       o      If the death occurred on 30 Heshvan, and  Heshvan  in  the  year
              after  the  death is chaser, then the jahrzeit is observed on 29
              Heshvan  in  years  when  Heshvan  is  chaser.   Otherwise,  the
              yahrzeit is observed on 1 Kislev when Heshvan is chaser.

       o      If the death occurred on 30 Kislev, and Kislev in the year after
              the death is chaser, then the jahrzeit is observed on 29  Kislev
              in  years  when  Kislev  is  chaser.  Otherwise, the yahrzeit is
              observed on 1 Tevet when Kislev is chaser.

       o      If the death occurred on 1-29 Adar A, it  is  observed  on  1-29
              Adar in non-leapyears.

       o      If  the  death occurred on 30 Adar A, it is observed on 30 Shvat
              in a non-leapyear.

       Specifying a Hebrew year for the jahr parameter causes the correct  be-
       haviour  to be selected for a death in that year.  You may also have to
       specify aflag, depending on your tradition.

       The jahrzeit information was supplied by Frank Yellin, who quoted  "The
       Comprehensive Hebrew Calendar" by Arthur Spier, and "Calendrical Calcu-
       lations" by E. M. Reingold and Nachum Dershowitz.

OUT-OF-BAND REMINDERS
       The SPECIAL keyword is used to transmit  "out-of-band"  information  to
       Remind  backends,  such as tkremind or Rem2PS.  They are used only when
       piping data from a remind -p line.  (Note that the COLOR special is  an
       exception;  it  downgrades  to the equivalent of MSG in remind's normal
       mode of operation.)

       The various SPECIALs recognized are particular for each  backend;  how-
       ever,  there are four SPECIALs that all backends should attempt to sup-
       port.  They are currently supported by Rem2PS, tkremind and rem2html.

       The SHADE special replaces the psshade() function.  Use it like this:
            REM Sat Sun SPECIAL SHADE 128
            REM Mon SPECIAL SHADE 255 0 0
       The SHADE keyword is followed by either one or three numbers, from 0 to
       255.   If  one  number  is  supplied, it is interpreted as a grey-scale
       value from black (0) to white (255).  If three  numbers  are  supplied,
       they  are  interpreted  as  RGB  components from minimum (0) to maximum
       (255).  The example above shades weekends a fairly dark grey and  makes
       Mondays  a  fully-saturated  red.   (These shadings appear in calendars
       produced by Rem2PS, tkremind and rem2html.)

       The MOON special replaces the psmoon() function.  Use it like this:
            REM [moondate(0)] SPECIAL MOON 0
            REM [moondate(1)] SPECIAL MOON 1
            REM [moondate(2)] SPECIAL MOON 2
            REM [moondate(3)] SPECIAL MOON 3
       These draw little moons on the various calendars.  The complete  syntax
       of the MOON special is as follows:
            ... SPECIAL MOON phase moonsize fontsize msg

       Phase  is  a  number from 0 to 3, with 0 representing a new moon, 1 the
       first quarter, 2 a full moon and 3 the last quarter.

       moonsize is the diameter in PostScript units of the moon to  draw.   If
       omitted or supplied as -1, the backend chooses an appropriate size.

       fontsize is the font size in PostScript units of the msg

       Msg is additional text that is placed near the moon glyph.

       Note  that  only the Rem2PS backend supports moonsize and fontsize; the
       other backends use fixed sizes.

       The COLOR special lets you place colored  reminders  in  the  calendar.
       Use it like this:

            REM ... SPECIAL COLOR 255 0 0 This is a bright red reminder
            REM ... SPECIAL COLOR 0 128 0 This is a dark green reminder

       You  can  spell  COLOR either the American way ("COLOR") or the British
       way ("COLOUR").  This manual will use the American way.

       Immediately following COLOR should be  three  decimal  numbers  ranging
       from 0 to 255 specifying red, green and blue intensities, respectively.
       The rest of the line is the text to put in the calendar.

       The COLOR special is "doubly special", because in its normal  operating
       mode,  remind  treats  a  COLOR  special just like a MSG-type reminder.
       Also, if you invoke Remind with -@[n],  then  it  approximates  SPECIAL
       COLOR reminders on your terminal.

       See  also the documentation of the $DefaultColor system variable in the
       section "SYSTEM VARIABLES".

       The WEEK special lets you place annotations such as the week number  in
       the  calendar.  For example, this would number each Monday with the ISO
       8601 week number.  The week number is shown like this: "(Wn)"  in  this
       example, but you can put whatever text you like after the WEEK keyword.

            REM Monday SPECIAL WEEK (W[weekno()])


MISCELLANEOUS
       COMMAND ABBREVIATIONS

       The following tokens can be abbreviated:

       o      REM  can be omitted - it is implied if no other valid command is
              present.

       o      CLEAR-OMIT-CONTEXT --> CLEAR

       o      PUSH-OMIT-CONTEXT --> PUSH

       o      POP-OMIT-CONTEXT --> POP

       o      DUMPVARS --> DUMP

       o      BANNER --> BAN

       o      INCLUDE --> INC

       o      SCANFROM --> SCAN

       NIFTY EXAMPLES

       This section is a sampling of what you can do with Remind.

            REM 5 Feb 1991 AT 14:00 +45 *30 \
            RUN mail -s "Meeting at %2" $LOGNAME </dev/null &

       On 5 February, 1991, this reminder will mail you reminders of a  2:00pm
       meeting  at  1:15, 1:45 and 2:00.  The subject of the mail message will
       be "Meeting at 2:00pm" and the body of the message will be blank.

            REM AT 17:00 RUN echo "5:00pm - GO HOME!" | xless -g +0+0 &

       This reminder will pop up an xless window at  5:00pm  every  day.   The
       xless window will contain the line "5:00pm - GO HOME!"

            REM AT 23:59 RUN (sleep 120; remind -a [filename()]) &

       This  reminder will run at one minute to midnight.  It will cause a new
       Remind process to start at one minute past midnight.  This  allows  you
       to have a continuous reminder service so you can work through the night
       and still get timed reminders for early in the morning.  Note that this
       trick is no longer necessary, providing you run Remind in daemon mode.

            remind -c12 /dev/null Jan 1993

       This  invocation  of Remind will cause it to print a calendar for 1993,
       with all entries left blank.

            REM CAL [trigdate()-date(year(trigdate()), 1, 1)+1]

       This example puts an entry in each box of a calendar showing the number
       (1-365 or 366) of the day of the year.

            REM Tue 2 Nov SATISFY (year(trigdate())%4) == 0
            IF trigvalid()
                 REM [trigdate()] ++5 MSG \
                 U.S. Presidential Election!!
            ENDIF

       This example warns you 5 days ahead of each American presidential elec-
       tion.  The first REM command calculates the  first  Tuesday  after  the
       first  Monday in November.  (This is equivalent to the first Tuesday on
       or after 2 November.)  The SATISFY clause ensures that the trigger date
       is issued only in election years, which are multiples of 4.  The second
       REM command actually issues the reminder.

       DETAILS ABOUT TRIGGER COMPUTATION

       Here is a conceptual description of how triggers are calculated.   Note
       that  Remind  actually  uses  a  much more efficient procedure, but the
       results are the same as if the conceptual procedure had been followed.

       Remind starts from the current date (that is, the value of today()) and
       scans  forward,  examining each day one at a time until it finds a date
       that satisfies the trigger, or can prove that  no  such  dates  (on  or
       later than today()) exist.

       If  Remind  is  executing  a  SATISFY-type  reminder,  it evaluates the
       expression with trigdate() set to the date found above.  If the expres-
       sion  evaluates  to zero or the null string, Remind continues the scan-
       ning procedure described above, starting with the day after the trigger
       found above.

       The  SCANFROM  clause (having a syntax similar to UNTIL) can modify the
       search strategy used.  In this case, Remind begins the scanning  proce-
       dure  at scan_date, which is the date specified in the SCANFROM clause.
       For example:

            REM Mon 1 SCANFROM 17 Jan 1992 MSG Foo

       The example above will always have a trigger date of Monday, 3 February
       1992.  That is because Remind starts scanning from 17 January 1992, and
       stops scanning as soon as it hits a date that satisfies "Mon 1."

       The main use of SCANFROM is in situations where you want  to  calculate
       the  positions  of  floating holidays.  Consider the Labour Day example
       shown much earlier.  Labour Day is the first Monday in  September.   It
       can move over a range of 7 days.  Consider the following sequence:

            REM Mon 1 Sept SCANFROM [today()-7] SATISFY 1
            OMIT [trigdate()]

            REM Mon AFTER MSG Hello

       The  SCANFROM clause makes sure that Remind begins scanning from 7 days
       before the current date.  This ensures that Labour Day for the  current
       year  will continue to be triggered until 7 days after it has occurred.
       This allows you to safely use the AFTER keyword as shown.

       As a special case, you can simply use a negative number after SCANFROM;
       a negative numbner -N is interpreted as N days before today.  Thus, the
       previous example could also be written like this:

            # This form of SCANFROM requires Remind 03.01.17 or later.
            REM Mon 1 Sept SCANFROM -7 SATISFY 1
            OMIT [trigdate()]

            REM Mon AFTER MSG Hello

       In general, use SCANFROM as shown for safe movable OMITs.   The  amount
       you  should  scan  back by (7 days in the example above) depends on the
       number of possible consecutive OMITted days that may occur, and on  the
       range of the movable holiday.  Generally, a value of 7 is safe.

       The  FROM  clause  operates  almost like the counterpoint to UNTIL.  It
       prevents the reminder from triggering before the FROM date.  For  exam-
       ple, the following reminder:

            REM Mon Thu FROM 23 Jul 2007 UNTIL 2 Aug 2007 MSG Test

       will trigger on Mondays and Thursdays between 23 July 2007 and 2 August
       2007 inclusive.

       FROM is really just syntactic sugar; you could implement  the  reminder
       above as follows:

            REM Mon Thu SCANFROM [max(today(), '2007-07-23')] \
                   UNTIL 2 Aug 2007 MSG Test

       but  that's  a  lot  harder  to  read.   Internally, Remind treats FROM
       exactly as illustrated using SCANFROM.  For that reason, you cannot use
       both FROM and SCANFROM.

       Note  that if you use one REM command to calculate a trigger date, per-
       form date calculations (addition or subtraction, for example) and  then
       use  the modified date in a subsequent REM command, the results may not
       be what you intended.  This is because you have circumvented the normal
       scanning  mechanism.  You should try to write REM commands that compute
       trigger dates that can be used unmodified in subsequent  REM  commands.
       The  file  "defs.rem"  that comes with the Remind distribution contains
       examples.

       DETAILS ABOUT TRIGVALID()

       The trigvalid() function returns 1 if Remind could find a trigger  date
       for  the previous REM or IFTRIG command.  More specifically, it returns
       1 if Remind finds a date not before the starting date of  the  scanning
       that  satisfies the trigger.  In addition, there is one special case in
       which trigvalid() returns 1 and trigdate() returns a meaningful result:

       If the REM or IFTRIG command did not contain an UNTIL clause, and  con-
       tained all of the day, month and year components, then Remind will cor-
       rectly compute a trigger date, even if it  happens  to  be  before  the
       start  of  scanning.  Note that this behaviour is not true for versions
       of Remind prior to 03.00.01.

AUTHOR
       Dianne Skoll <dianne@skoll.ca> wrote Remind.  The moon code was  copied
       largely  unmodified  from  "moontool"  by John Walker.  The sunrise and
       sunset functions use ideas from programs by Michael Schwartz  and  Marc
       T. Kaufman.  The Hebrew calendar support was taken from "hdate" by Amos
       Shapir.  OS/2 support was done by Darrel Hankerson,  Russ  Herman,  and
       Norman  Walsh.   The  supported foreign languages and their translators
       are listed below.  Languages marked "complete" support  error  messages
       and  usage  instructions  in that language; all others only support the
       substitution filter mechanism and month/day names.

       German -- Wolfgang Thronicke

       Dutch -- Willem Kasdorp and Erik-Jan Vens

       Finnish -- Mikko Silvonen (complete)

       French -- Laurent Duperval (complete)

       Norwegian -- Trygve Randen

       Danish -- Mogens Lynnerup

       Polish -- Jerzy Sobczyk (complete)

       Brazilian Portuguese -- Marco Paganini (complete)

       Italian -- Valerio Aimale

       Romanian -- Liviu Daia

       Spanish -- Rafa Couto

       Icelandic -- Bjrn Davsson

BUGS
       There's no good reason why read-only system variables  are  not  imple-
       mented  as  functions,  or  why functions like version(), etc.  are not
       implemented as read-only system variables.

       Hebrew dates in Remind change at midnight instead of sunset.

       Language should be selectable at  run-time,  not  compile-time.   Don't
       expect this to happen soon!

       Remind has some built-in limits (for example, number of global OMITs.)

BIBLIOGRAPHY
       Nachum  Dershowitz  and Edward M. Reingold, "Calendrical Calculations",
       Software-Practice and Experience, Vol. 20(9), Sept. 1990, pp 899-928.

       L. E. Doggett, Almanac  for  computers  for  the  year  1978,  Nautical
       Almanac Office, USNO.

       Richard Siegel and Michael and Sharon Strassfeld, The First Jewish Cat-
       alog, Jewish Publication Society of America.

SEE ALSO
       rem, rem2ps, tkremind



4th Berkeley Distribution       1 January 2020                       REMIND(1)