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at(1)				 User Commands				 at(1)

NAME
       at, batch - execute commands at a later time

SYNOPSIS
       at [-c |	-k | -s]  [-m] [-f file] [-p project] [-q queuename] -t	time

       at  [-c	|  -k  | -s]  [-m] [-f file] [-p project] [-q queuename] time-
       spec...

       at -l [-p project] [-q queuename] [ at_job_id. ..]

       at -r at_job_id.	..

       batch [-p project]

DESCRIPTION
   at
       The at utility reads commands  from  standard  input  and  groups  them
       together	as an at-job, to be executed at	a later	time.

       The at-job will be executed in a	separate invocation of the shell, run-
       ning in a separate process group	with no	controlling  terminal,	except
       that  the  environment  variables, current working directory, file cre-
       ation mask (see umask(1)), and system resource limits (for sh  and  ksh
       only,  see ulimit(1)) in	effect when the	at utility is executed will be
       retained	and used when the at-job is executed.

       When the	at-job is submitted, the  at_job_id  and  scheduled  time  are
       written	to standard error. The at_job_id is an identifier that will be
       a string	consisting solely of alphanumeric characters  and  the	period
       character.  The	at_job_id  is  assigned	 by the	system when the	job is
       scheduled such that it uniquely identifies a particular job.

       User notification and the processing of the job's standard  output  and
       standard	error are described under the -m option.

       Users  are  permitted  to  use  at  and batch (see below) if their name
       appears in the file  /usr/lib/cron/at.allow.  If	 that  file  does  not
       exist,  the  file  /usr/lib/cron/at.deny	is checked to determine	if the
       user should be denied access to at. If neither file exists, only	a user
       with the	solaris.jobs.user authorization	is allowed to submit a job. If
       only at.deny exists and	is  empty,  global  usage  is  permitted.  The
       at.allow	and at.deny files consist of one user name per line.

       cron  and  at  jobs  will  be  not be executed if the user's account is
       locked. Only accounts which are not locked as defined in	shadow(4) will
       have their job or process executed.

   batch
       The  batch utility reads	commands to be executed	at a later time. It is
       the equivalent of the command:

       at -q b -m now
       where queue b is	a special at queue, specifically for batch jobs. Batch
       jobs will be submitted to the batch queue for immediate execution.

OPTIONS
       The  following  options are supported. If the -c, -k, or	-s options are
       not specified, the SHELL	environment  variable  by  default  determines
       which shell to use.

       -c    C shell. csh(1) is	used to	execute	the at-job.

       -k    Korn shell. ksh(1)	is used	to execute the at-job.

       -s    Bourne shell. sh(1) is used to execute the	at-job.

       -f file
	     Specifies	the path of a file to be used as the source of the at-
	     job, instead of standard input.

       -l    (The letter ell.) Reports all jobs	 scheduled  for	 the  invoking
	     user  if  no  at_job_id operands are specified. If	at_job_ids are
	     specified,	reports	only information for these jobs.

       -m    Sends mail	to  the	 invoking  user	 after	the  at-job  has  run,
	     announcing	 its  completion.  Standard  output and	standard error
	     produced by the at-job will be mailed to the user as well,	unless
	     redirected	 elsewhere. Mail will be sent even if the job produces
	     no	output.

	     If	-m is not used,	the job's standard output and  standard	 error
	     will  be  provided	 to the	user by	means of mail, unless they are
	     redirected	elsewhere; if there is no such output to provide,  the
	     user is not notified of the job's completion.

       -p project
	     Specifies	under  which  project the at or	batch job will be run.
	     When used with the	-l option, limits the search to	that  particu-
	     lar  project.  Values  for	project	will be	interpreted first as a
	     project name, and then as a  possible  project  ID,  if  entirely
	     numeric. By default, the user's current project is	used.

       -q queuename
	     Specifies	in  which queue	to schedule a job for submission. When
	     used with the -l option, limits the  search  to  that  particular
	     queue. Values for queuename are limited to	the lower case letters
	     a through z. By default, at-jobs will be scheduled	in queue a. In
	     contrast,	queue  b  is reserved for batch	jobs. Since queue c is
	     reserved for cron jobs, it	can not	be used	with the -q option.

       -r at_job_id
	     Removes the jobs with the specified at_job_id operands that  were
	     previously	scheduled by the at utility.

       -t time
	     Submits  the  job	to  be	run  at	the time specified by the time
	     option-argument, which must have the format as specified  by  the
	     touch(1) utility.

OPERANDS
       The following operands are supported:

       at_job_id
	     The  name	reported by a previous invocation of the at utility at
	     the time the job was scheduled.

       timespec
	     Submit the	job to be run at the date and time specified.  All  of
	     the  timespec  operands are interpreted as	if they	were separated
	     by	space characters and  concatenated.  The  date	and  time  are
	     interpreted  as  being in the timezone of the user	(as determined
	     by	the TZ variable), unless a timezone name appears  as  part  of
	     time below.

	     In	the "C"	locale,	the following describes	the three parts	of the
	     time specification	string.	All of the  values  from  the  LC_TIME
	     categories	in the "C" locale are recognized in a case-insensitive
	     manner.

	     time  The time can	be specified as	one, two or four digits.  One-
		   and	two-digit  numbers  are	 taken to be hours, four-digit
		   numbers to be hours and minutes. The	time can alternatively
		   be  specified  as two numbers separated by a	colon, meaning
		   hour:minute.	An AM/PM indication (one of  the  values  from
		   the am_pm keywords in the LC_TIME locale category) can fol-
		   low the time; otherwise, a 24-hour  clock  time  is	under-
		   stood.  A timezone name of GMT, UCT,	or ZULU	(case insensi-
		   tive) can follow to specify that the	time is	in Coordinated
		   Universal Time.  Other timezones can	be specified using the
		   TZ environment variable. The	time field can also be one  of
		   the following tokens	in the "C" locale:

		   midnight
			 Indicates the time 12:00 am (00:00).

		   noon	 Indicates the time 12:00 pm.

		   now	 Indicate  the	current	 day and time. Invoking	at now
			 will submit an	at-job for potentially immediate  exe-
			 cution	(that is, subject only to unspecified schedul-
			 ing delays).

	     date  An optional date can	be specified as	either	a  month  name
		   (one	 of  the  values from the mon or abmon keywords	in the
		   LC_TIME locale category) followed by	a day number (and pos-
		   sibly year number preceded by a comma) or a day of the week
		   (one	of the values from the day or abday  keywords  in  the
		   LC_TIME  locale  category). Two special days	are recognized
		   in the "C" locale:

	     today Indicates the current day.

	     tomorrow
		   Indicates the day following the current day.

	     If	no date	is given, today	 is  assumed  if  the  given  time  is
	     greater  than  the	current	time, and tomorrow is assumed if it is
	     less. If the given	month is less than the current month  (and  no
	     year is given), next year is assumed.

       increment
	     The  optional  increment  is a number preceded by a plus sign (+)
	     and suffixed by one  of  the  following:  minutes,	 hours,	 days,
	     weeks,  months,  or  years.  (The	singular  forms	 will  be also
	     accepted.)	The keyword next is equivalent to an increment	number
	     of	+ 1. For example, the following	are equivalent commands:

	     at	2pm + 1	week
	     at	2pm next week

USAGE
       The format of the at command line shown here is guaranteed only for the
       "C" locale. Other locales are not supported for	midnight,  noon,  now,
       mon,  abmon,  day, abday, today,	tomorrow, minutes, hours, days,	weeks,
       months, years, and next.

       Since the commands run in a separate shell  invocation,	running	 in  a
       separate	process	group with no controlling terminal, open file descrip-
       tors, traps and priority	inherited from the  invoking  environment  are
       lost.

EXAMPLES
   at
       Example 1: Typical sequence at a	terminal

       This sequence can be used at a terminal:

       $ at -m 0730 tomorrow
       sort < file >outfile
       <EOT>

       Example 2: Redirecting output

       This sequence, which demonstrates redirecting standard error to a pipe,
       is useful in a command procedure	(the sequence  of  output  redirection
       specifications is significant):

       $ at now	+ 1 hour <<!
       diff file1 file2	2>&1 >outfile |	mailx mygroup

       Example 3: Self-rescheduling a job

       To  have	a job reschedule itself, at can	be invoked from	within the at-
       job. For	example, this "daily-processing" script	 named	my.daily  will
       run  every day (although	crontab	is a more appropriate vehicle for such
       work):

       # my.daily runs every day
       at now tomorrow < my.daily
       daily-processing

       Example 4: Various time and operand presentations

       The spacing of the three	portions of the	"C" locale timespec  is	 quite
       flexible	as long	as there are no	ambiguities. Examples of various times
       and operand presentations include:

       at 0815am Jan 24
       at 8 :15amjan24
       at now "+ 1day"
       at 5 pm FRIday
       at '17
	    utc+
	    30minutes'

   batch
       Example 5: Typical sequence at a	terminal

       This sequence can be used at a terminal:

       $ batch
       sort <file >outfile
       <EOT>

       Example 6: Redirecting output

       This sequence, which demonstrates redirecting standard error to a pipe,
       is  useful  in  a command procedure (the	sequence of output redirection
       specifications is significant):

       $ batch <<!
       diff file1 file2	2>&1 >outfile |	mailx mygroup
       !

ENVIRONMENT VARIABLES
       See environ(5) for descriptions of the following	environment  variables
       that  affect  the  execution  of	 at and	batch: LC_CTYPE,  LC_MESSAGES,
       NLSPATH,	 and LC_TIME.

       SHELL Determine a name of a command interpreter to be  used  to	invoke
	     the at-job. If the	variable is unset or NULL, sh will be used. If
	     it	is set to a value other	than sh, the implementation  will  use
	     that  shell;  a  warning diagnostic will be printed telling which
	     shell will	be used.

       TZ    Determine the timezone. The job will be submitted	for  execution
	     at	 the  time  specified  by  timespec or -t time relative	to the
	     timezone specified	by the TZ variable.  If	timespec  specifies  a
	     timezone,	it  will  override  TZ.	If timespec does not specify a
	     timezone and TZ is	unset or NULL, an unspecified default timezone
	     will be used.

       DATEMSK
	     If	the environment	variable DATEMSK is set, at will use its value
	     as	the full path  name  of	 a  template  file  containing	format
	     strings.  The strings consist of format specifiers	and text char-
	     acters that are used to provide a richer set  of  allowable  date
	     formats  in  different  languages	by appropriate settings	of the
	     environment variable LANG or LC_TIME. The list of allowable  for-
	     mat  specifiers  is  located  in the getdate(3C) manual page. The
	     formats described in the OPERANDS section for the time  and  date
	     arguments,	 the  special  names noon, midnight, now, next,	today,
	     tomorrow, and the increment  argument  are	 not  recognized  when
	     DATEMSK is	set.

EXIT STATUS
       The following exit values are returned:

       0     The at utility successfully submitted, removed or listed a	job or
	     jobs.

       >0    An	error occurred,	and the	job will not be	scheduled.

FILES
       /usr/lib/cron/at.allow
	     names of users, one per line, who are authorized access to	the at
	     and batch utilities

       /usr/lib/cron/at.deny
	     names of users, one per line, who are denied access to the	at and
	     batch utilities

ATTRIBUTES
       See attributes(5) for descriptions of the following attributes:

   at
       +-----------------------------+-----------------------------+
       |      ATTRIBUTE	TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Availability		     |SUNWcsu			   |
       +-----------------------------+-----------------------------+
       |CSI			     |Not enabled		   |
       +-----------------------------+-----------------------------+

   batch
       +-----------------------------+-----------------------------+
       |      ATTRIBUTE	TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Availability		     |SUNWesu			   |
       +-----------------------------+-----------------------------+
       |CSI			     |Enabled			   |
       +-----------------------------+-----------------------------+

SEE ALSO
       auths(1),  crontab(1),  csh(1),	date(1),  ksh(1),   sh(1),   touch(1),
       ulimit(1),  umask(1),  cron(1M),	 getdate(3C), auth_attr(4), shadow(4),
       attributes(5), environ(5)

NOTES
       Regardless of queue used, cron(1M) has a	limit of 100 jobs in execution
       at any time.

       There  can  be  delays  in  cron	at job execution. In some cases, these
       delays can compound to the point	that cron job processing appears to be
       hung.  All jobs will be executed	eventually. When the delays are	exces-
       sive, the only workaround is to kill and	restart	cron.

SunOS 5.9			  11 Jan 2002				 at(1)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | OPERANDS | USAGE | EXAMPLES | ENVIRONMENT VARIABLES | EXIT STATUS | FILES | ATTRIBUTES | SEE ALSO | NOTES

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