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     AT(1)                                                       AT(1)

          at - execute commands at a later time

          at time [ day ] [ file ]

          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.

          /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

          calendar(1), pwd(1), sleep(1), cron(8)d times out of range.

          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.