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at(1) [v7 man page]

AT(1)							      General Commands Manual							     AT(1)

NAME
at - execute commands at a later time SYNOPSIS
at time [ day ] [ file ] DESCRIPTION
At squirrels away a copy of the named file (standard input default) to be used as input to sh(1) at a specified later time. A cd(1) com- mand to the current directory is inserted at the beginning, followed by assignments to all environment variables. When the script is run, it uses the user and group ID of the creator of the copy file. The time is 1 to 4 digits, with an optional following `A', `P', `N' or `M' for AM, PM, noon or midnight. One and two digit numbers are taken to be hours, three and four digits to be hours and minutes. If no letters follow the digits, a 24 hour clock time is understood. The optional day is either (1) a month name followed by a day number, or (2) a day of the week; if the word `week' follows invocation is moved seven days further off. Names of months and days may be recognizably truncated. Examples of legitimate commands are at 8am jan 24 at 1530 fr week At programs are executed by periodic execution of the command /usr/lib/atrun from cron(8). The granularity of at depends upon how often atrun is executed. Standard output or error output is lost unless redirected. FILES
/usr/spool/at/yy.ddd.hhhh.uu activity to be performed at hour hhhh of year day ddd of year yy. uu is a unique number. /usr/spool/at/lasttimedone contains hhhh for last hour of activity. /usr/spool/at/past directory of activities now in progress /usr/lib/atrun program that executes activities that are due pwd(1) SEE ALSO
calendar(1), cron(8) DIAGNOSTICS
Complains about various syntax errors and times out of range. BUGS
Due to the granularity of the execution of /usr/lib/atrun, there may be bugs in scheduling things almost exactly 24 hours into the future. AT(1)

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AT(1)							    BSD General Commands Manual 						     AT(1)

NAME
at, batch, atq, atrm -- queue, examine, or delete jobs for later execution SYNOPSIS
at [-q queue] [-f file] [-mldbv] time at [-q queue] [-f file] [-mldbv] -t [[CC]YY]MMDDhhmm[.SS] at -c job [job ...] at -l [job ...] at -l -q queue at -r job [job ...] atq [-q queue] [-v] atrm job [job ...] batch [-q queue] [-f file] [-mv] [time] DESCRIPTION
The at and batch utilities read commands from standard input or a specified file. The commands are executed at a later time, using sh(1). 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; atrm deletes jobs; batch executes commands when system load levels permit; in other words, when the load average drops below _LOADAVG_MX (1.5), or the value specified in the invocation of atrun. The at utility allows some moderately complex time specifications. It accepts times of the form HHMM or HH:MM to run a job at a specific time of day. (If that time is already past, the next day is assumed.) As an alternative, the following keywords may be specified: midnight, noon, or teatime (4pm) and time-of-day may be suffixed with AM or PM for running in the morning or the evening. The day on which the job is to be run may also be specified by giving a date in the form month-name day with an optional year, or giving a date of the forms DD.MM.YYYY, DD.MM.YY, MM/DD/YYYY, MM/DD/YY, MMDDYYYY, or MMDDYY. The specification of a date must follow the specification of the time of day. Time can also be specified as: [now] + count time-units, where the time-units can be minutes, hours, days, weeks, months or years and at may be told 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, use at 4pm + 3 days, to run a job at 10:00am on July 31, use at 10am Jul 31 and to run a job at 1am tomorrow, use at 1am tomorrow. The at utility also supports the POSIX time format (see -t option). For both at and batch, commands are read from standard input or the file specified with the -f option. The working directory, the environ- ment (except for the variables TERM, TERMCAP, 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 sendmail(8). 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 _PERM_PATH/at.allow and _PERM_PATH/at.deny. If the file _PERM_PATH/at.allow exists, only usernames mentioned in it are allowed to use at. In these two files, a user is considered to be listed only if the user name has no blank or other characters before it on its line and a newline character immediately after the name, even at the end of the file. Other lines are ignored and may be used for comments. If _PERM_PATH/at.allow does not exist, _PERM_PATH/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. IMPLEMENTATION NOTES
Note that at is implemented through the launchd(8) daemon periodically invoking atrun(8), which is disabled by default. See atrun(8) for information about enabling atrun. OPTIONS
-b Is an alias for batch. -c Cat the jobs listed on the command line to standard output. -d Is an alias for atrm (this option is deprecated; use -r instead). -f file Read the job from file rather than standard input. -l With no arguments, list all jobs for the invoking user. If one or more job numbers are given, list only those jobs. -m Send mail to the user when the job has completed even if there was no output. -q queue Use the specified queue. A queue designation consists of a single letter; valid queue designations range from a to z and A to Z. The _DEFAULT_AT_QUEUE queue (a) is the default for at and the _DEFAULT_BATCH_QUEUE queue (b) is the default for batch. Queues with higher letters run with increased niceness. 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. -r Remove the specified jobs. -t Specify the job time using the POSIX time format. The argument should be in the form [[CC]YY]MMDDhhmm[.SS] where each pair of let- ters represents the following: CC The first two digits of the year (the century). YY The second two digits of the year. MM The month of the year, from 1 to 12. DD the day of the month, from 1 to 31. hh The hour of the day, from 0 to 23. mm The minute of the hour, from 0 to 59. SS The second of the minute, from 0 to 61. If the CC and YY letter pairs are not specified, the values default to the current year. If the SS letter pair is not specified, the value defaults to 0. -v For atq, shows completed but not yet deleted jobs in the queue; otherwise shows the time the job will be executed. FILES
_ATJOB_DIR directory containing job files (/usr/lib/cron/jobs/) _ATJOB_DIR/_LOCKFILE job-creation lock file (/usr/lib/cron/jobs/...) _ATSPOOL_DIR directory containing output spool files (/usr/lib/cron/spool/) _PERM_PATH/at.allow allow permission control (/usr/lib/cron/at.allow) _PERM_PATH/at.deny deny permission control (/usr/lib/cron/at.deny) /var/run/utmpx login records SEE ALSO
nice(1), sh(1), umask(2), compat(5), atrun(8), cron(8), sendmail(8) BUGS
If the file /var/run/utmpx 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 at and batch utilities as presently implemented are not suitable when users are competing for resources. If this is the case, another batch system such as nqs may be more suitable. Specifying a date past 2038 may not work on some systems. AUTHORS
At was mostly written by Thomas Koenig <ig25@rz.uni-karlsruhe.de>. The time parsing routines are by David Parsons <orc@pell.chi.il.us>, with minor enhancements by Joe Halpin <joe.halpin@attbi.com>. BSD
January 13, 2002 BSD
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