at [-V] [-q queue] [-f file] [-mldbv] TIME
at command is used to schedule jobs for later execution.
at either takes the commands to be executed from the standard input, stopping when it encounters end of file (entered manually by typing
control-d), or from the file specified after the
at takes a time specification in the 24 hour
HH:MM form, the 12 hour time folowed by AM or PM, or
teatime(4:00 PM); if you do not provide the date it is assumed that you mean the next occorance of the specified time (today is assumed unless the time has past in which case tomorow is assumed).
If you do not wish the next occorance of the specified time the date can be given to
at. If you want the job to run today (or not run if the time specified has past) you can specify
tomorow can also be used if you want the job to run tomorow. The date can be specified in the form 'month-name day' with an optional year,
DD.MM.YY. The date specification must always follow the time specification.
You can also give a time in the form
now + n
[hours minutes days weeks]
The user who invokes the
at command is mailed the standard output and standard error using
Weather or not a user can invoke the
at command is specified by the existance of their username in the files
/etc/at.allow existes than no user who is not specified in the file can invoke the
at command, otherwise if the file
/etc/at.deny exists then any user not specified in the
/etc/at.deny file can invoke
at. If neither of the files exist then only the superuser can use the
at command. An empty
/etc/at.deny means that every user is allowed use these commands in general, this is the default configuration.