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uschedule(1)		    General Commands Manual		  uschedule(1)

NAME
       uschedule - uschedule a job

SYNOPSIS
       uschedule [OPTIONS] ID TIMESPEC [...]

DESCRIPTION
       uschedule  schedules  the command with the identifier ID	to be executed
       at the time specified by	 TIMESPEC.  Multiple  TIMESPEC	arguments  are
       allowed.

       ID   is	 the  identifier  of  a	 command  previously  registered  with
       uschedulecmd(1).

OPTIONS

       -., --dot-as-home
	      The current working directory will be used instead of $HOME.

       -1, --null1
	      Redirect the standard  output  of	 the  job  to  /dev/null.  The
	      default  is  to  write it	into the log file of the uscheduled(8)
	      daemon.

       -2, --null2
	      Redirect the standard error output of the	job to /dev/null.  The
	      same default applies.

       -c, --count=NNN
	      Repeat  the  command up to NNN times. A value of 1 means the the
	      job will run once, 0 is a	synonym	 for  forever,	which  is  the
	      default.

       -d, --dir=DIR
	      Put the new job into DIR.	The default is ~/.uschedule/.

       -D, --description=DESC
	      Give  the	 new job the description DESC. The description is used
	      for   the	  user	 interface   commands	uschedulelist(1)   and
	      uschedulerm(1)  only.   Descriptions  must not be	longer than 70
	      characters and must not contain colons.

       -e, --every=NUMBER[mhdw]
	      Repeat every NUMBER time units (default: seconds).

	      This option is implemented in such a  way	 that  the  NUMBER  is
	      added once at the	start of a search. Then	all other restrictions
	      (late, from, to, TIMESPEC) will be applied and the next matching
	      time  will be searched for. In other words: The start time to be
	      searched from is changed from now	to now + NUMBER.

	      A	m (h, d	or w) appended to NUMBER changes the  time  unit  from
	      seconds to minutes (hours, days or weeks).

       -f, --from=TIMESPEC
	      Jobs will	only be	started	if TIMESPEC has	matched. This together
	      with  the	--to option allows to further restrict the times a job
	      will be started. This example starts a job JOBID every day a few
	      seconds after midnight, but only after the first of april, 2004,
	      has been reached:

	  uschedule --from "2003-4-1 00:00:00" JOBID '*-*-* 00:00:10'

	      TIMESPEC should be simple. Wild cards are	only  allowed  at  the
	      start,   not  after  any	fixed  number.	2002-*-1  00:00:00  is
	      forbidden, *-*-* *:00:00 is OK.

	      Weekday names may	be used, too, though the result	is  likely  to
	      be non-intuitive.	Better avoid them.

	      This option was added in version 0.6.0.

       -l, --late=SECONDS
	      Allow  the job to	be executed up to SECONDS late.	This is	useful
	      if the machine or	the uscheduled(8) daemon was down  during  the
	      time the job should have run.

	      The default is 3600 seconds (one hour).

       -t, --to=TIMESPEC
	      Jobs will	only be	started	if TIMESPEC has	not been reached. This
	      together	with  the --from option	allows to further restrict the
	      times a job will be started. The	example	 below	starts	a  job
	      every  day  a few	seconds	after midnight,	but only up to 30th of
	      march, 2004:

	  uschedule --to "2003-4-1 00:00:00" jobid '*-*-* 00:00:10'

	      TIMESPEC should be simple. Wild cards are	only  allowed  at  the
	      start,   not  after  any	fixed  number.	2002-*-1  00:00:00  is
	      forbidden, *-*-* *:00:00 is OK.  If wild	cards  are  used,  the
	      --from option has	to be used, to.

	      Weekday  names  may be used, too,	though the result is likely to
	      be non-intuitive.	Better avoid them.

	      This option was added in version 0.6.0.

TIMESPEC
       A time specification  consists  of  two	or  three  words.  The	first,
       optional,  words	 specifies a day-of-week, the next the year, month and
       day-of-month, and the last word specifies hour, minute and seconds.
       Words are separated by exactly one space.

   Day Of Week
       The day of the week is given as a comma separated list of weekday names
       or three	letter abbreviations thereof. Names are	case insensitive.  The
       default is to run the job at any	day of the week.

       Sunday,Wed is a valid list. Monday, Tues	isn't.

   Date
       The date	consists of three parts: Year, month and day.  Two  parts  are
       separated by a single dash. Each	part is	a numerical value as described
       below.

   Time
       The time	consists of three parts, too. Hour, minute and second are by a
       single colon. Each part is a numerical value as described below.

   Number Specification
       Whenever	 is number is allowed in a job execution time specification is
       may be either a single value, a single star ("*", meaning "all possible
       values")	or a comma separated list of values.
       A value may be a	number or a number ("a") followed by a slash  followed
       by  a  number  ("b"),  meaning  "execute	 at  'a+b*n'",	where "n" is a
       positive	integer	including 0). You may use a plus sign instead  of  the
       slash ('a+b').
       Note  that  30/10  (oder	 30+10)	 and  such things are understood quite
       literally, meaning "30, 40, 50" and not "0, 10, 20, 30, 40, 50".

   Examples
       The following schedules a job to	be run at midnight of each seventh  of
       the month:
	  *-*-7	00:00:00

       To run a	job on every monday in december	at 12:00:00:

	  Monday *-12-*	12:00:00

       To  run	a  job 30 minutes and 45 seconds after each full hour on every
       monday and friday if that day is	the first or third day of the month in
       the months january, march, may, juli, september and november:

	  mon,fri *-1/2-1,3 *:30:45

   Incomplete time specs
       uschedule attempts to complete the TIMESPECs, except for	the --from  or
       --to ones. *- is	used when year or month	is missing, * is used when the
       day  is	missing,  and  *:  is used when	hour or	minute are missing. If
       there is	no time	given at all, then 0:0:0 is used. Examples:

	 03-05 08:05:40	     ->	*-03-05	08:05:40
	 05 08:05:40	     ->	*-*-05 08:05:40
	 08:05:40	     ->	*-*-* 08:05:40
	 05:40		     ->	*-*-* *:05:40
	 40		     ->	*-*-* *:*:40
	 Sat,Sun 05 08:05:40 ->	Sat,Sun	*-*-05 08:05:40
	 Sat,Sun 08:05:40    ->	Sat,Sun	*-*-* 08:05:40
	 2003-03-05 05:40    ->	2003-03-05 *:05:40
	 2003-03-05	     ->	2003-03-05 0:0:0
	 03-05		     ->	*-03-05	0:0:0

TIME OFFSET
       An argument consisting of a plus	sign and one to	four numbers separated
       by colons (+[[[dd:]hh:]mm:]ss) means to	start  the  job	 once  in  the
       future,	at  the	 time  reached	with  the current time is added	to the
       argument. dd is the offset in days, hh in hours,	mm in minutes  und  ss
       stands for seconds. That	is,
	 uschedule test	+1:0:0:0
	 uschedule test	+24:0:0
	 uschedule test	+1440:0
	 uschedule test	+86400
       all start the job "test"	exactly	one day	after uschedule	is executed.

DIFFERENCES
       The  unix  cron	daemon	executes a job if either day or	week or	day of
       month matches.  uscheduled(8) executes it if both match.	The is no  way
       to completely mimic either logic	with the other software.

       Unix  cron  often needs a separated at daemon to	execute	one-time-jobs.
       This is nothing more than a design problem in cron.

       Unix also provides a batch command, which executes jobs if  the	system
       load  is	low. This is often implemented inside the at daemon. uschedule
       doesn't provide a way to	emulate	this (note  that  batch	 is  pointless
       anyway:	if you just have a short job then you might as well run	it, it
       doesn't matter. If you have a long and resource-intensive job and don't
       want your job to	eat resources when there's a  shortage	of  them  then
       batch  provides	no  way	to temporarily suspend a job during this time.
       If the resource in question is not system load  but  memory,  disk-  or
       network-bandwidth then batch doesn't help you).

       Unix  cron  doesn't support second granularity. uschedule does this for
       only one	reason:	to help	to avoid that all jobs of all users  start  in
       the same	second and overload the	system.

AUTHOR
       Uwe Ohse, uwe@ohse.de

SEE ALSO
       uschedulecmd(1),	uschedule_intro(7).

       The homepage may	be more	up-to-date, see
       http://www.ohse.de/uwe/uschedule.html.

uschedule			     0.7.1			  uschedule(1)

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