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| Newer page: | version 2 | Last edited on Monday, August 2, 2004 9:22:40 pm | by CraigBox | |
| Older page: | version 1 | Last edited on Tuesday, June 4, 2002 12:21:46 am | by perry | Revert |
@@ -1,238 +1,75 @@
-AT
-!!!AT
-NAME
-SYNOPSIS
-DESCRIPTION
-OPTIONS
-FILES
-SEE ALSO
-BUGS
-AUTHOR
-----
!!NAME
+at, batch, atq, atrm - queue, examine or delete jobs for later execution
-
-at, batch, atq, atrm - queue, examine or delete jobs for later execution
!!SYNOPSIS
+__at__ [[ __-V__ ] [[ __-q__ ''queue'' ] [[ __-f__ ''file'' ] [[ __-mldbv__ ] __TIME__ %%%
+__at -c__ ''job'' [[ ''job...'' ] %%%
+__atq__ [[ __-V__ ] [[ __-q__ ''queue'' ] %%%
+__atrm__ [[ __-V__ ] ''job'' [[ ''job...'' ] %%%
+__batch__ [[ __-V__ ] [[ __-q__ ''queue'' ] [[ __-f__ ''file'' ] [[ __-mv__ ] [[ __TIME__ ]
-
-__at__ [[__-V__] [[__-q__ ''queue''] [[__-f__
-''file''] [[__-mldbv__] __TIME
-at -c__ ''job'' [[''job...'']__
-atq__ [[__-V__] [[__-q__ ''queue'']__
-atrm__ [[__-V__] ''job'' [[''job...'']__
-batch__ [[__-V__] [[__-q__ ''queue''] [[__-f__
-''file''] [[__-mv__] [[__TIME__]
!!DESCRIPTION
+__at__ and __batch__ read commands from standard input or a specified file which are to be executed at a later time, using __/bin/sh__ .
+;__at__ : executes commands at a specified time.
+;__atq__ : lists the user's pending jobs, unless the user is the superuser; in that case, everybody's jobs are listed. The format of the output lines (one for each job) is: Job number, date, hour, job class.
+;__atrm__ : deletes jobs, identified by their job number.
+;__batch__ : executes commands when system load levels permit; in other words, when the load average drops below 0.8, or the value specified in the invocation of __atrun__ .
+__At__ allows fairly complex time specifications, extending the POSIX.2 standard. It accepts times of the form __HH:MM__ to run a job at a specific time of day. (If that time is already past, the next day is assumed.) You may also specify __midnight,__ __noon,__ or teatime(4pm) and you can have a time-of-day suffixed with __AM__ or __PM__ for running in the morning or the evening. You can also say what day the job will be run, by giving a date in the form __month-name__ __day__ with an optional __year,__ or giving a date of the form __MMDDYY__ or __MM/DD/YY__ or __DD.MM.YY.__ The specification of a date ''must'' follow the specification of the time of day. You can also give times like __now__ __+__ ''count'' ''time-units,'' where the time-units can be __minutes,__ __hours,__ __days,__ or __weeks__ and you can tell __at__ to run the job today by suffixing the time with __today__ and to run the job tomorrow by suffixing the time with __tomorrow.__
-__at__ and
__batch
__ read commands from standard input
-or a specified file which are
to be executed at
a later
-time
, using
__/bin/sh
__.
+For example, to run a job at 4pm three days from now, you would do
__at 4pm + 3 days,
__ to run a job at 10:00am on July 31, you would do
__at 10am Jul 31
__ and
to run
a job at 1am tomorrow
, you would do
__at 1am tomorrow.
__
+The exact definition of the time specification can be found in ''/usr/share/doc/at-3.1.8/timespec'' .
-__at__
+For both
__at__ and __batch__ , commands are read from standard input or the file specified with the __-f__ option and executed. The working directory, the environment (except for the variables __TERM__ , __DISPLAY__ and _____ ) and the umask are retained from the time of invocation. An __at __ - or __batch __ - command invoked from a su(1) shell will retain the current userid. The user will be mailed standard error and standard output from his commands, if any. Mail will be sent using the command __/usr/sbin/sendmail__ . If __at__ is executed from a su(1) shell, the owner of the login shell will receive the mail.
+The superuser may use these commands in any case. For other users, permission to use at is determined by the files ''/etc/at.allow'' and ''/etc/at.deny'' .
-executes commands
at a specified time
.
+If the file ''/etc/
at.allow'' exists, only usernames mentioned in it are allowed to use __at__
.
+If ''/etc/at.allow'' does not exist, ''/etc/at.deny'' is checked, every username not mentioned in it is then allowed to use __at__ .
-__atq__
+If neither exists, only the superuser is allowed use of at.
+An empty ''/etc/at.deny'' means that every user is allowed use these commands, this is the default configuration.
-lists the user's pending jobs, unless the user is the
-superuser; in that case, everybody's jobs are listed. The
-format of the output lines (one for each job) is: Job
-number, date, hour, job class.
-
-
-__atrm__
-
-
-deletes jobs, identified by their job number.
-
-
-__batch__
-
-
-executes commands when system load levels permit; in other
-words, when the load average drops below 1.5, or the value
-specified in the invocation of __atrun__.
-
-
-__At__ allows fairly complex time specifications,
-extending the POSIX.2 standard. It accepts times of the form
-__HH:MM__ to run a job at a specific time of day. (If
-that time is already past, the next day is assumed.) You may
-also specify __midnight, noon,__ or __teatime__ (4pm)
-and you can have a time-of-day suffixed with __AM__ or
-__PM__ for running in the morning or the evening. You can
-also say what day the job will be run, by giving a date in
-the form __month-name day__ with an optional __year,__
-or giving a date of the form __MMDDYY__ or
-__MM/DD/YY__ or __DD.MM.YY.__ The specification of a
-date ''must'' follow the specification of the time of
-day. You can also give times like __now +__ ''count
-time-units,'' where the time-units can be __minutes,
-hours, days,__ or __weeks__ and you can tell __at__
-to run the job today by suffixing the time with __today__
-and to run the job tomorrow by suffixing the time with
-__tomorrow.__
-
-
-For example, to run a job at 4pm three days from now, you
-would do __at 4pm + 3 days,__ to run a job at 10:00am on
-July 31, you would do __at 10am Jul 31__ and to run a job
-at 1am tomorrow, you would do __at 1am
-tomorrow.__
-
-
-The exact definition of the time specification can be found
-in ''/usr/share/doc/at/timespec''.
-
-
-For both __at__ and __batch__, commands are read from
-standard input or the file specified with the __-f__
-option and executed. The working directory, the environment
-(except for the variables __TERM__, __DISPLAY__ and
-_____) and the umask are retained from the time of
-invocation. An __at__ - or __batch__ - command invoked
-from a __su(1)__ shell will retain the current userid.
-The user will be mailed standard error and standard output
-from his commands, if any. Mail will be sent using the
-command __/usr/sbin/sendmail__. If __at__ is executed
-from a __su(1)__ shell, the owner of the login shell will
-receive the mail.
-
-
-The superuser may use these commands in any case. For other
-users, permission to use at is determined by the files
-''/etc/at.allow'' and ''/etc/at.deny''.
-
-
-If the file ''/etc/at.allow'' exists, only usernames
-mentioned in it are allowed to use __at__.
-
-
-If ''/etc/at.allow'' does not exist, ''/etc/at.deny''
-is checked, every username not mentioned in it is then
-allowed to use __at__.
-
-
-If neither exists, only the superuser is allowed use of
-at.
-
-
-An empty ''/etc/at.deny'' means that every user is
-allowed use these commands, this is the default
-configuration.
!!OPTIONS
+;__-V__ : prints the version number to standard error.
+;__-q__ '' queue'' : uses the specified queue. A queue designation consists of a single letter; valid queue designations range from __a__ to __z__ . and __A__ to __Z__ . The __a__ queue is the default for __at__ and the __b__ queue for __batch__ . Queues with higher letters run with increased niceness. The special queue "=" is reserved for jobs which are currently running.
-__-V
__
+If a job is submitted to a queue designated with an uppercase letter, it is treated as if it had been submitted to batch at that time. If __atq__ is given a specific queue, it will only show jobs pending in that queue.
+;
__-m__ : Send mail to the user when the job has completed even if there was no output.
+;__-f__ '' file'' : Reads the job from __file__ rather than standard input.
+;__-l__ : Is an alias for __atq.__
+;__-d__ : Is an alias for __atrm.
__
+;__-v__ : Shows the time the job will be executed.
-prints
the version number
to standard error
.
+Times displayed will be in
the format "1997-02-20 14:50" unless the environment variable __POSIXLY_CORRECT __ is set; then, it will be "Thu Feb 20 14:50:00 1996".
+;.B : -c cats the jobs listed on the command line
to standard output
.
-
-__-q__ ''queue''
-
-
-uses the specified queue. A queue designation consists of a
-single letter; valid queue designations range from __a__
-to __z__. and __A__ to __Z__. The __a__ queue is
-the default for __at__ and the __b__ queue for
-__batch__. Queues with higher letters run with increased
-niceness. The special queue
-__
-
-
-If a job is submitted to a queue designated with an
-uppercase letter, it is treated as if it had been submitted
-to batch at that time. If __atq__ is given a specific
-queue, it will only show jobs pending in that
-queue.
-
-
-__-m__
-
-
-Send mail to the user when the job has completed even if
-there was no output.
-
-
-__-f__ ''file''
-
-
-Reads the job from __file__ rather than standard
-input.
-
-
-__-l__
-
-
-Is an alias for __atq.__
-
-
-__-d__
-
-
-Is an alias for __atrm.__
-
-
-__-v__
-
-
-Shows the time the job will be executed.
-
-
-Times displayed will be in the format
-POSIXLY_CORRECT__ is set; then, it will be
-__
-
-
-__-c__
-
-
-cats the jobs listed on the command line to standard
-output.
!!FILES
+''/var/spool/at''
+''/var/spool/at/spool''
+''/proc/loadavg''
+''/var/run/utmp''
+''/etc/at.allow''
+''/etc/at.deny''
-
-''/var/spool/cron/atjobs
-/var/spool/cron/atspool
-/proc/loadavg
-/var/run/utmp
-/etc/at.allow
-/etc/at.deny''
!!SEE ALSO
+cron(1), nice(1), sh(1), umask(2), atd(8).
-
-cron(1), nice(1), sh(1),
-umask(2), atd(8).
!!BUGS
+The correct operation of __batch__ for Linux depends on the presence of a ''proc'' - type directory mounted on ''/proc'' .
+If the file ''/var/run/utmp'' is not available or corrupted, or if the user is not logged on at the time __at__ is invoked, the mail is sent to the userid found in the environment variable __LOGNAME__ . If that is undefined or empty, the current userid is assumed.
-The correct operation of
__batch__ for Linux depends on
-the presence of a ''proc''- type directory mounted on
-''/proc''
.
-
-
-the file ''/var/run/utmp''
is not available or
-corrupted, or if
the user is not logged on at the time
-__at__ is invoked
, the mail is sent
to the userid found
-in the environment variable
__LOGNAME
__. If that is
-undefined or empty, the current userid is
-assumed.
-
+__At__ and
__batch__ as presently implemented are not suitable when users are competing
for resources
. If this
is the case for your site
, you might want
to consider another batch system, such as
__nqs
__ .
-__At__ and __batch__ as presently implemented are not
-suitable when users are competing for resources. If this is
-the case for your site, you might want to consider another
-batch system, such as __nqs__.
!!AUTHOR
+At was mostly written by Thomas Koenig, ig25@rz.uni-karlsruhe.de.
+!!HOW TO SIMPLY USE THE BLOODY THING
-At was mostly written by Thomas Koenig,
-ig25@rz.uni-karlsruhe.de.
-----
+ $ echo foo | at 2am
