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(1) 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/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

     AT(1)                                                       AT(1)

          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.