path: root/usr/src/man/man1/at.1

'\" te
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.TH AT 1 "Apr 13, 2005"
.SH NAME
at, batch \- execute commands at a later time
.SH SYNOPSIS
.LP
.nf
\fB/usr/bin/at\fR [\fB-c\fR | \fB-k\fR | \fB-s\fR] [\fB-m\fR] [\fB-f\fR \fIfile\fR] [\fB-p\fR \fIproject\fR]
     [\fB-q\fR \fIqueuename\fR] \fB-t\fR \fItime\fR
.fi

.LP
.nf
\fB/usr/bin/at\fR [\fB-c\fR | \fB-k\fR | \fB-s\fR] [\fB-m\fR] [\fB-f\fR \fIfile\fR] [\fB-p\fR \fIproject\fR]
     [\fB-q\fR \fIqueuename\fR] \fItimespec\fR...
.fi

.LP
.nf
\fB/usr/bin/at\fR \fB-l\fR [\fB-p\fR \fIproject\fR] [\fB-q\fR \fIqueuename\fR] [\fIat_job_id\fR \fI...\fR]
.fi

.LP
.nf
\fB/usr/bin/at\fR \fB-r\fR \fIat_job_id\fR \fI...\fR
.fi

.LP
.nf
\fB/usr/bin/batch\fR [\fB-p\fR \fIproject\fR]
.fi

.LP
.nf
\fB/usr/xpg4/bin/at\fR [\fB-c\fR | \fB-k\fR | \fB-s\fR] [\fB-m\fR] [\fB-f\fR \fIfile\fR] [\fB-p\fR \fIproject\fR]
     [\fB-q\fR \fIqueuename\fR] \fB-t\fR \fItime\fR
.fi

.LP
.nf
\fB/usr/xpg4/bin/at\fR [\fB-c\fR | \fB-k\fR | \fB-s\fR] [\fB-m\fR] [\fB-f\fR \fIfile\fR] [\fB-p\fR \fIproject\fR]
     [\fB-q\fR \fIqueuename\fR] \fItimespec\fR...
.fi

.LP
.nf
\fB/usr/xpg4/bin/at\fR \fB-l\fR [\fB-p\fR \fIproject\fR] [\fB-q\fR \fIqueuename\fR]
     [\fIat_job_id\fR \fI...\fR]
.fi

.LP
.nf
\fB/usr/xpg4/bin/at\fR \fB-r\fR \fIat_job_id\fR \fI...\fR
.fi

.LP
.nf
\fB/usr/xpg4/bin/batch\fR [\fB-p\fR \fIproject\fR]
.fi

.SH DESCRIPTION
.SS "at"
.sp
.LP
The \fBat\fR utility reads commands from standard input and groups them
together as an \fIat-job\fR, to be executed at a later time.
.sp
.LP
The at-job is executed in a separate invocation of the shell, running in a
separate process group with no controlling terminal, except that the
environment variables, current working directory, file creation mask (see
\fBumask\fR(1)), and system resource limits (for \fBsh\fR and \fBksh\fR only,
see \fBulimit\fR(1)) in effect when the \fBat\fR utility is executed is
retained and used when the at-job is executed.
.sp
.LP
When the at-job is submitted, the \fIat_job_id\fR and scheduled time are
written to standard error. The \fIat_job_id\fR is an identifier that is a
string consisting solely of alphanumeric characters and the period character.
The \fIat_job_id\fR is assigned by the system when the job is scheduled such
that it uniquely identifies a particular job.
.sp
.LP
User notification and the processing of the job's standard output and standard
error are described under the \fB-m\fR option.
.sp
.LP
Users are permitted to use \fBat\fR and \fBbatch\fR (see below) if their name
appears in the file \fB/usr/lib/cron/at.allow\fR. If that file does not exist,
the file \fB/usr/lib/cron/at.deny\fR is checked to determine if the user should
be denied access to \fBat\fR. If neither file exists, only a user with the
\fBsolaris.jobs.user\fR authorization is allowed to submit a job. If only
\fBat.deny\fR exists and is empty, global usage is permitted. The
\fBat.allow\fR and \fBat.deny\fR files consist of one user name per line.
.sp
.LP
\fBcron\fR and \fBat\fR jobs are not be executed if the user's account is
locked. Only accounts which are not locked as defined in \fBshadow\fR(4) will
have their job or process executed.
.SS "batch"
.sp
.LP
The \fBbatch\fR utility reads commands to be executed at a later time.
.sp
.LP
Commands of the forms:
.sp
.in +2
.nf
/usr/bin/batch [-p project]
/usr/xpg4/bin/batch [-p project]
.fi
.in -2
.sp

.sp
.LP
are respectively equivalent to:
.sp
.in +2
.nf
/usr/bin/at -q b [-p project] now
/usr/xpg4/bin/at -q b -m [-p project] now
.fi
.in -2
.sp

.sp
.LP
where queue \fBb\fR is a special \fBat\fR queue, specifically for batch jobs.
Batch jobs are submitted to the batch queue for immediate execution. Execution
of submitted jobs can be delayed by limits on the number of jobs allowed to run
concurrently. See \fBqueuedefs\fR(4).
.SH OPTIONS
.sp
.LP
If the \fB-c\fR, \fB-k\fR, or \fB-s\fR options are not specified, the
\fBSHELL\fR environment variable by default determines which shell to use.
.sp
.LP
If \fBSHELL\fR is unset or \fBNULL\fR, \fB/usr/bin/sh\fR is used.
.sp
.LP
The following options are supported:
.sp
.ne 2
.na
\fB\fB-c\fR \fR
.ad
.RS 17n
C shell. \fBcsh\fR(1) is used to execute the at-job.
.RE

.sp
.ne 2
.na
\fB\fB-k\fR \fR
.ad
.RS 17n
Korn shell. \fBksh\fR(1) is used to execute the at-job.
.RE

.sp
.ne 2
.na
\fB\fB-s\fR \fR
.ad
.RS 17n
Bourne shell. \fBsh\fR(1) is used to execute the at-job.
.RE

.sp
.ne 2
.na
\fB\fB-f\fR \fIfile\fR \fR
.ad
.RS 17n
Specifies the path of a file to be used as the source of the at-job, instead of
standard input.
.RE

.sp
.ne 2
.na
\fB\fB-l\fR \fR
.ad
.RS 17n
(The letter ell.) Reports all jobs scheduled for the invoking user if no
\fIat_job_id\fR operands are specified. If \fIat_job_id\fRs are specified,
reports only information for these jobs.
.RE

.sp
.ne 2
.na
\fB\fB-m\fR \fR
.ad
.RS 17n
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 are
mailed to the user as well, unless redirected elsewhere. Mail is sent even if
the job produces no output.
.sp
If \fB-m\fR is not used, the job's standard output and standard error is
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.
.RE

.sp
.ne 2
.na
\fB\fB-p\fR \fIproject\fR\fR
.ad
.RS 17n
Specifies under which project the \fBat\fR or \fBbatch\fR job is run. When used
with the \fB-l\fR option, limits the search to that particular project. Values
for \fIproject\fR is interpreted first as a project name, and then as a
possible project \fBID\fR, if entirely numeric. By default, the user's current
project is used.
.RE

.sp
.ne 2
.na
\fB\fB-q\fR \fIqueuename\fR \fR
.ad
.RS 17n
Specifies in which queue to schedule a job for submission. When used with the
\fB-l\fR option, limits the search to that particular queue. Values for
\fIqueuename\fR are limited to the lower case letters \fBa\fR through \fBz\fR.
By default, at-jobs are scheduled in queue \fBa\fR. In contrast, queue \fBb\fR
is reserved for batch jobs. Since queue \fBc\fR is reserved for cron jobs, it
can not be used with the \fB-q\fR option.
.RE

.sp
.ne 2
.na
\fB\fB-r\fR \fIat_job_id\fR \fR
.ad
.RS 17n
Removes the jobs with the specified \fIat_job_id\fR operands that were
previously scheduled by the \fBat\fR utility.
.RE

.sp
.ne 2
.na
\fB\fB-t\fR \fItime\fR \fR
.ad
.RS 17n
Submits the job to be run at the time specified by the \fItime\fR
option-argument, which must have the format as specified by the \fBtouch\fR(1)
utility.
.RE

.SH OPERANDS
.sp
.LP
The following operands are supported:
.sp
.ne 2
.na
\fB\fIat_job_id\fR \fR
.ad
.RS 14n
The name reported by a previous invocation of the \fBat\fR utility at the time
the job was scheduled.
.RE

.sp
.ne 2
.na
\fB\fItimespec\fR \fR
.ad
.RS 14n
Submit the job to be run at the date and time specified. All of the
\fItimespec\fR 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 \fBTZ\fR variable), unless a
timezone name appears as part of \fItime\fR below.
.sp
In the "C" locale, the following describes the three parts of the time
specification string. All of the values from the \fBLC_TIME\fR categories in
the "C" locale are recognized in a case-insensitive manner.
.sp
.ne 2
.na
\fB\fItime\fR \fR
.ad
.RS 14n
The \fItime\fR 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 \fIhour\fR\fB:\fR\fIminute\fR. An AM/PM indication (one of the values
from the \fBam_pm\fR keywords in the \fBLC_TIME\fR locale category) can follow
the time; otherwise, a 24-hour clock time is understood. A timezone name of
\fBGMT\fR, \fBUCT\fR, or \fBZULU \fR(case insensitive) can follow to specify
that the time is in Coordinated Universal Time.  Other timezones can be
specified using the \fBTZ\fR environment variable. The \fItime\fR field can
also be one of the following tokens in the "C" locale:
.sp
.ne 2
.na
\fB\fBmidnight\fR \fR
.ad
.RS 13n
Indicates the time 12:00 am (00:00).
.RE

.sp
.ne 2
.na
\fB\fBnoon\fR \fR
.ad
.RS 13n
Indicates the time 12:00 pm.
.RE

.sp
.ne 2
.na
\fB\fBnow\fR \fR
.ad
.RS 13n
Indicate the current day and time. Invoking \fBat\fR \fBnow\fR submits an
at-job for potentially immediate execution (that is, subject only to
unspecified scheduling delays).
.RE

.RE

.sp
.ne 2
.na
\fB\fIdate\fR \fR
.ad
.RS 14n
An optional \fIdate\fR can be specified as either a month name (one of the
values from the \fBmon\fR or \fBabmon\fR keywords in the \fBLC_TIME\fR locale
category) followed by a day number (and possibly year number preceded by a
comma) or a day of the week (one of the values from the \fBday\fR or
\fBabday\fR keywords in the \fBLC_TIME\fR locale category). Two special days
are recognized in the "C" locale:
.sp
.ne 2
.na
\fB\fBtoday\fR \fR
.ad
.RS 13n
Indicates the current day.
.RE

.sp
.ne 2
.na
\fB\fBtomorrow\fR \fR
.ad
.RS 13n
Indicates the day following the current day.
.RE

If no \fIdate\fR is given, \fBtoday\fR is assumed if the given time is greater
than the current time, and \fBtomorrow\fR 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.
.RE

.sp
.ne 2
.na
\fB\fIincrement\fR \fR
.ad
.RS 14n
The optional \fIincrement\fR is a number preceded by a plus sign (\fB+\fR) and
suffixed by one of the following: \fBminutes\fR, \fBhours\fR, \fBdays\fR,
\fBweeks\fR, \fBmonths\fR, or \fByears\fR. (The singular forms are also
accepted.) The keyword \fBnext\fR is equivalent to an increment number of \fB+
1\fR. For example, the following are equivalent commands:
.sp
.in +2
.nf
\fBat 2pm + 1 week
at 2pm next week\fR
.fi
.in -2
.sp

.RE

.RE

.SH USAGE
.sp
.LP
The format of the \fBat\fR command line shown here is guaranteed only for the
"C" locale. Other locales are not supported for \fBmidnight\fR, \fBnoon\fR,
\fBnow\fR, \fBmon\fR, \fBabmon\fR, \fBday\fR, \fBabday\fR, \fBtoday\fR,
\fBtomorrow\fR, \fBminutes\fR, \fBhours\fR, \fBdays\fR, \fBweeks\fR,
\fBmonths\fR, \fByears\fR, and \fBnext\fR.
.sp
.LP
Since the commands run in a separate shell invocation, running in a separate
process group with no controlling terminal, open file descriptors, traps and
priority inherited from the invoking environment are lost.
.SH EXAMPLES
.SS "at"
.LP
\fBExample 1 \fRTypical Sequence at a Terminal
.sp
.LP
This sequence can be used at a terminal:

.sp
.in +2
.nf
$ at \(mim 0730 tomorrow
sort < file >outfile
<EOT>
.fi
.in -2
.sp

.LP
\fBExample 2 \fRRedirecting Output
.sp
.LP
This sequence, which demonstrates redirecting standard error to a pipe, is
useful in a command procedure (the sequence of output redirection
specifications is significant):

.sp
.in +2
.nf
$ at now + 1 hour <<!
diff file1 file2 2>&1 >outfile | mailx mygroup
.fi
.in -2
.sp

.LP
\fBExample 3 \fRSelf-rescheduling a Job
.sp
.LP
To have a job reschedule itself, \fBat\fR can be invoked from within the
at-job. For example, this "daily-processing" script named \fBmy.daily\fR runs
every day (although \fBcrontab\fR is a more appropriate vehicle for such work):

.sp
.in +2
.nf
# my.daily runs every day
at now tomorrow < my.daily
daily-processing
.fi
.in -2
.sp

.LP
\fBExample 4 \fRVarious Time and Operand Presentations
.sp
.LP
The spacing of the three portions of the "C" locale \fItimespec\fR is quite
flexible as long as there are no ambiguities. Examples of various times and
operand presentations include:

.sp
.in +2
.nf
at 0815am Jan 24
at 8 :15amjan24
at now "+ 1day"
at 5 pm FRIday
at '17
	utc+
	30minutes'
.fi
.in -2
.sp

.SS "batch"
.LP
\fBExample 5 \fRTypical Sequence at a Terminal
.sp
.LP
This sequence can be used at a terminal:

.sp
.in +2
.nf
$ batch
sort <file >outfile
<EOT>
.fi
.in -2
.sp

.LP
\fBExample 6 \fRRedirecting Output
.sp
.LP
This sequence, which demonstrates redirecting standard error to a pipe, is
useful in a command procedure (the sequence of output redirection
specifications is significant):

.sp
.in +2
.nf
$ batch <<!
diff file1 file2 2>&1 >outfile | mailx mygroup
!
.fi
.in -2
.sp

.SH ENVIRONMENT VARIABLES
.sp
.LP
See \fBenviron\fR(5) for descriptions of the following environment variables
that affect the execution of \fBat\fR and \fBbatch\fR: \fBLANG\fR,
\fBLC_ALL\fR, \fBLC_CTYPE\fR,  \fBLC_MESSAGES\fR,  \fBNLSPATH\fR, and
\fBLC_TIME\fR.
.sp
.ne 2
.na
\fB\fBDATEMSK\fR \fR
.ad
.RS 12n
If the environment variable \fBDATEMSK\fR is set, \fBat\fR uses its value as
the full path name of a template file containing format strings. The strings
consist of format specifiers and text characters that are used to provide a
richer set of allowable date formats in different languages by appropriate
settings of the environment variable \fBLANG\fR or \fBLC_TIME\fR. The list of
allowable format specifiers is located in the \fBgetdate\fR(3C) manual page.
The formats described in the \fBOPERANDS\fR section for the \fItime\fR and
\fIdate\fR arguments, the special names \fBnoon\fR, \fBmidnight\fR, \fBnow\fR,
\fBnext\fR, \fBtoday\fR, \fBtomorrow\fR, and the \fIincrement\fR argument are
not recognized when \fBDATEMSK\fR is set.
.RE

.sp
.ne 2
.na
\fB\fBSHELL\fR \fR
.ad
.RS 12n
Determine a name of a command interpreter to be used to invoke the at-job. If
the variable is unset or \fINULL\fR, \fBsh\fR is used. If it is set to a value
other than \fBsh\fR, the implementation uses that shell; a warning diagnostic
is printed telling which shell will be used.
.RE

.sp
.ne 2
.na
\fB\fBTZ\fR \fR
.ad
.RS 12n
Determine the timezone. The job is submitted for execution at the time
specified by \fItimespec\fR or \fB-t\fR \fItime\fR relative to the timezone
specified by the \fBTZ\fR variable. If \fItimespec\fR specifies a timezone, it
overrides \fBTZ\fR. If \fItimespec\fR does not specify a timezone and \fBTZ\fR
is unset or \fINULL\fR, an unspecified default timezone is used.
.RE

.SH EXIT STATUS
.sp
.LP
The following exit values are returned:
.sp
.ne 2
.na
\fB\fB0\fR \fR
.ad
.RS 7n
The \fBat\fR utility successfully submitted, removed or listed a job or jobs.
.RE

.sp
.ne 2
.na
\fB\fB>0\fR \fR
.ad
.RS 7n
An error occurred, and the job will not be scheduled.
.RE

.SH FILES
.sp
.ne 2
.na
\fB\fB/usr/lib/cron/at.allow\fR \fR
.ad
.RS 27n
names of users, one per line, who are authorized access to the \fBat\fR and
\fBbatch\fR utilities
.RE

.sp
.ne 2
.na
\fB\fB/usr/lib/cron/at.deny\fR \fR
.ad
.RS 27n
names of users, one per line, who are denied access to the \fBat\fR and
\fBbatch\fR utilities
.RE

.SH ATTRIBUTES
.sp
.LP
See \fBattributes\fR(5) for descriptions of the following attributes:
.SS "/usr/bin/at"
.sp

.sp
.TS
box;
c | c
l | l .
ATTRIBUTE TYPE	ATTRIBUTE VALUE
_
CSI	Not enabled
_
Interface Stability	Standard
.TE

.SS "/usr/xpg4/bin/at"
.sp

.sp
.TS
box;
c | c
l | l .
ATTRIBUTE TYPE	ATTRIBUTE VALUE
_
CSI	Not enabled
_
Interface Stability	Standard
.TE

.SS "/usr/bin/batch"
.sp

.sp
.TS
box;
c | c
l | l .
ATTRIBUTE TYPE	ATTRIBUTE VALUE
_
CSI	Enabled
_
Interface Stability	Standard
.TE

.SS "/usr/xpg4/bin/batch"
.sp

.sp
.TS
box;
c | c
l | l .
ATTRIBUTE TYPE	ATTRIBUTE VALUE
_
CSI	Enabled
_
Interface Stability	Standard
.TE

.SH SEE ALSO
.sp
.LP
\fBauths\fR(1), \fBcrontab\fR(1), \fBcsh\fR(1), \fBdate\fR(1), \fBksh\fR(1),
\fBsh\fR(1), \fBtouch\fR(1), \fBulimit\fR(1), \fBumask\fR(1), \fBcron\fR(1M),
\fBgetdate\fR(3C), \fBauth_attr\fR(4), \fBshadow\fR(4), \fBqueuedefs\fR(4),
\fBattributes\fR(5), \fBenviron\fR(5), \fBstandards\fR(5)
.SH NOTES
.sp
.LP
Regardless of queue used, \fBcron\fR(1M) has a limit of 100 jobs in execution
at any time.
.sp
.LP
There can be delays in \fBcron\fR at job execution. In some cases, these delays
can compound to the point that \fBcron\fR job processing appears to be hung.
All jobs are executed eventually. When the delays are excessive, the only
workaround is to kill and restart \fBcron\fR.