V10/man/man1/at.1

.TH AT 1
.CT 1 time_man
.SH NAME
at \(mi execute commands at a later time
.SH SYNOPSIS
.B at
[
.B -r
]
.I time
[
.I day
]
[
.I file
]
.PP
.B at -l
.SH DESCRIPTION
.I At
squirrels away a copy of the named
.I file
(standard input default)
to be used as input to
.IR sh (1)
at a specified later time.
A
.I 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 userid and groupid
of the creator of the copy.
.PP
The
.I time
is 1 to 4 digits, with an optional following
.LR A ,
.LR P ,
.L N
or 
.L 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.
.PP
The optional
.I day
is either a month name followed by a day number,
or a day of the week; if the word
.L week
follows, invocation is moved seven days further off.
Names of months and days may be recognizably truncated.
A year number, spelled out in full, may follow the month.
.PP
The options are
.TP
.B -r
Remove the specified activity.
.TP
.B -l
List all activities scheduled for this user.
.PP
.I At
programs are executed by periodic execution
of
.F /usr/lib/atrun
from
.IR cron (8).
The granularity of
.I at
depends upon how often
.I atrun
is executed.
.PP
The standard output and standard error files are lost unless redirected.
.SH EXAMPLES
.EX
at 0800 dec 24
echo ho ho ho | mail claus
.EE
.TP
.L
at -r `at -l`
Remove a scheduled activity.
.SH FILES
.TF /usr/spool/at/yy.ddd.hhmm
.TP
.F /usr/lib/atrun
.TP
.BI  /usr/spool/at/ yy . ddd . hhmm\fP.*
activity for year, day, hour
.TP
.F /usr/spool/at/lasttimedone
last
.I hhmm
.TP
.F /usr/spool/at/past
activities in progress
.SH "SEE ALSO"
.IR calendar (1),
.IR pwd (1),
.IR sleep (1),
.IR cron (8)
.SH BUGS
Due to the granularity of the execution of
.I atrun,
there may be bugs in scheduling things almost
exactly 24 hours into the future.