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CRONTAB(1)		     Cronie Users' Manual		    CRONTAB(1)



NAME
       crontab - maintain crontab files for individual users

SYNOPSIS
       crontab [-u user] file
       crontab [-u user] [-l | -r | -e] [-i] [-s]

DESCRIPTION
       Crontab	is the program used to install, remove or list the tables used
       to drive the cron(8) daemon.  Each user can have their own crontab, and
       though  these  are  files  in /var/spool/ , they are not intended to be
       edited directly. For SELinux in mls mode can be even  more  crontabs  -
       for each range. For more see selinux(8).

       The cron jobs could be allow or disallow for different users. For clas-
       sical  crontab  there  exists  cron.allow  and  cron.deny  files.    If
       cron.allow  file exists, then you must be listed therein in order to be
       allowed to use this command.  If the cron.allow file does not exist but
       the  cron.deny  file  does  exist,  then	 you must not be listed in the
       cron.deny file in order to use this command.  If neither of these files
       exists,	only  the super user will be allowed to use this command.  The
       second option is using PAM authentication,  where  you  set  up	users,
       which  could  or	 couldn't  use	crontab and also system cron jobs from
       /etc/cron.d/.

       The temporary directory could be set in enviroment variables.  If  it's
       not set by user than /tmp is used.

OPTIONS
       -u     Append  the name of the user whose crontab is to be tweaked.  If
	      this option is not given, crontab examines "your" crontab, i.e.,
	      the  crontab  of	the  person  executing the command.  Note that
	      su(8) can confuse crontab and that if you are running inside  of
	      su(8)  you  should  always  use the -u option for safety's sake.
	      The first form of this command is used to install a new  crontab
	      from  some  named	 file or standard input if the pseudo-filename
	      "-" is given.

       -l     The current crontab will be displayed on standard output.

       -r     The current crontab will be removed.

       -e     This option is used to edit the current crontab using the editor
	      specified	 by the VISUAL or EDITOR environment variables.	 After
	      you exit from the editor, the modified crontab will be installed
	      automatically.

       -i     This  option  modifies  the  -r  option to prompt the user for a
	      'y/Y' response before actually removing the crontab.

       -s     It will append the current SELinux security context string as an
	      MLS_LEVEL	 setting to the crontab file before editing / replace-
	      ment occurs - see the documentation of MLS_LEVEL in crontab(5).

SEE ALSO
       crontab(5),cron(8)

FILES
       /etc/cron.allow
       /etc/cron.deny

STANDARDS
       The crontab command conforms to IEEE Std1003.2-1992 (``POSIX'').	  This
       new  command  syntax  differs  from previous versions of Vixie Cron, as
       well as from the classic SVR3 syntax.

DIAGNOSTICS
       A fairly informative usage message appears if you run  it  with	a  bad
       command line.

AUTHOR
       Paul Vixie <vixie@isc.org>



Marcela Malaova			 20 July 2009			    CRONTAB(1)