at \- execute commands at a later time
squirrels away a copy of the named
at a specified later time.
command to the current directory is inserted
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.
is 1 to 4 digits, with an optional following
AM, PM, noon or midnight.
One and two digit numbers are taken to be hours, three and four digits
If no letters follow the digits, a 24 hour clock time is understood.
(1) a month name followed by a day number,
(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
programs are executed by periodic execution
Standard output or error output is lost unless redirected.
/usr/spool/at/yy.ddd.hhhh.uu
activity to be performed at hour
/usr/spool/at/lasttimedone contains
for last hour of activity.
/usr/spool/at/past directory of activities now in progress
/usr/lib/atrun program that executes activities that
Complains about various syntax errors and times out of range.
Due to the granularity of the execution of
there may be bugs in scheduling things almost
exactly 24 hours into the future.