# crontab(1)

    NAME
         crontab - User crontab manipulation

    SYNOPSIS
         crontab -c [user] file
         crontab -l [user]
         crontab -r [user]
         crontab -p

    DESCRIPTION
         The crontab program allows users to  manipulate  their  personal  crontab
         files.   These files are hidden in /usr/spool/crontabs/user where user is
         the login name of a given  user.   The  system  daemon  cron  uses  these
         crontabs,  among  others, to run tasks that are to be repeated at regular
         intervals.  See crontab(5) on what a good crontab file should look like.

         Only the superuser can specify a user name to manipulate the crontab of a
         given user.  Any other user can only touch their own crontab file.

    OPTIONS

         -c [user] file
              Install file as the crontab file of user.

         -l [user]
              List the crontab file of user to standard output.

         -r [user]
              Remove the crontab file of user.

         -p   Tell cron to reload its tables.  Useful for system administrators to
              signal a change to any of the system crontab files.  Changes made by
              the crontab program are signalled automatically.   (Mnemonic:  -p  =
              "ping".)

    FILES

         /usr/spool/crontabs/user     Per user personal crontab file.

    SEE ALSO
         crontab(5), cron(8).

    DIAGNOSTICS
         Crontab preparses a new crontab and only installs  it  if  correct.   All
         errors  are sent to standard error, messages about installing a new table
         and telling cron to reload are sent to standard output.

    BUGS
         Crontab misses a -e option that other  implementations  of  this  command
         allow  one  to  edit  the  current crontab and install the result.  Seems
         quite handy until you try to install a  new  crontab  from  an  automated
         script.  That's why this command has a -c option that installs a prepared
         crontab file.  Use

              crontab -l >/tmp/tab
              ${EDITOR-vi} /tmp/tab
              crontab -c /tmp/tab

         to get the same effect as crontab -e.

    AUTHOR
         Kees J. Bot (kjb@cs.vu.nl)