AT(1) 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 command 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 com-
mand /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/lib/atrun executor (run by cron(8)).
in /usr/spool/at:
yy.ddd.hhhh.* activity for year yy, day dd, hour hhhh.
lasttimedone last hhhh
past activities in progress
SEE ALSO
calendar(1), pwd(1), sleep(1), cron(8)d 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.