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crontab(1)			 User Commands			    crontab(1)

NAME
       crontab - user crontab file

SYNOPSIS
       crontab [filename]

       crontab [-elr] username

DESCRIPTION
       The crontab utility manages a user's access with	cron (see cron(1M)) by
       copying,	creating, listing, and	removing  crontab  files.  If  invoked
       without	options,  crontab  copies  the specified file, or the standard
       input if	no file	is specified, into a directory that holds  all	users'
       crontabs.

       If  crontab  is	invoked	with filename, this will overwrite an existing
       crontab entry for the user that invokes it.

   crontab Access Control
       Users: Access to	crontab	is allowed:

	  o  if	the user's name	appears	in /etc/cron.d/cron.allow.

	  o  if	/etc/cron.d/cron.allow does not	exist and the user's  name  is
	     not in /etc/cron.d/cron.deny.

       Users: Access to	crontab	is denied:

	  o  if	 /etc/cron.d/cron.allow	 exists	 and the user's	name is	not in
	     it.

	  o  if	/etc/cron.d/cron.allow does not	exist and user's  name	is  in
	     /etc/cron.d/cron.deny.

	  o  if	 neither  file	exists,	only a user with the solaris.jobs.user
	     authorization is allowed to submit	a job.

       Notice that the rules for allow and deny	apply  to  root	 only  if  the
       allow/deny files	exist.

       The allow/deny files consist of one user	name per line.

   crontab Entry Format
       A  crontab  file	 consists  of lines of six fields each.	The fields are
       separated by spaces or tabs. The	first five are integer	patterns  that
       specify the following:

       minute (0-59),
       hour (0-23),
       day of the month	(1-31),
       month of	the year (1-12),
       day of the week (0-6 with 0=Sunday).

       Each  of	 these	patterns may be	either an asterisk  (meaning all legal
       values) or a list of elements separated by commas. An element is	either
       a number	or two numbers separated by a minus sign (meaning an inclusive
       range). Note that the specification of days may be made by  two	fields
       (day  of	 the month and day of the week). Both are adhered to if	speci-
       fied as a list of elements. See EXAMPLES.

       The sixth field of a line in a crontab file is a	string	that  is  exe-
       cuted  by the shell at the specified times. A percent character in this
       field (unless escaped by	\) is translated to a NEWLINE character.

       Only the	first line (up to a `%'	or end of line)	of the	command	 field
       is executed by the shell. Other lines are made available	to the command
       as standard input. Any line beginning with a `#'	is a comment and  will
       be ignored. The file should not contain blank lines.

       The  shell  is  invoked	from  your $HOME directory with	an arg0	of sh.
       Users who desire	to have	their .profile executed	must explicitly	do  so
       in  the	crontab	 file.	cron  supplies a default environment for every
       shell, defining HOME,  LOGNAME,	SHELL(=/bin/sh),  TZ,  and  PATH.  The
       default	PATH  for  user	 cron  jobs  is	/usr/bin; while	root cron jobs
       default	to  /usr/sbin:/usr/bin.	 The  default  PATH  can  be  set   in
       /etc/default/cron; see cron(1M).

       If  you	do not redirect	the standard output and	standard error of your
       commands, any generated output or errors	will be	mailed to you.

OPTIONS
       The following options are supported:

       -e    Edits a copy of the current user's	crontab	file,  or  creates  an
	     empty  file  to  edit  if crontab does not	exist. When editing is
	     complete, the file	is installed as	the user's crontab file. If  a
	     username  is  given, the specified	user's crontab file is edited,
	     rather than the current user's crontab file;  this	 may  only  be
	     done  by  a  user with the	solaris.jobs.admin authorization.  The
	     environment variable EDITOR determines which  editor  is  invoked
	     with  the -e option. The default editor is	ed(1). Notice that all
	     crontab jobs should be submitted using crontab;  you  should  not
	     add  jobs	by just	editing	the crontab file because cron will not
	     be	aware of changes made this way.

	     If	all lines in the crontab file are  deleted,  the  old  crontab
	     file  will	be restored. The correct way to	delete all lines is to
	     remove the	crontab	file via the -r	option.

       -l    Lists the crontab file for	the invoking user. Only	 a  user  with
	     the  solaris.jobs.admin authorization can specify a username fol-
	     lowing the	-r or -l options to remove or list the crontab file of
	     the specified user.

       -r    Removes a user's crontab from the crontab directory.

EXAMPLES
       Example 1: Cleaning up core files

       This example cleans up core files every weekday morning at 3:15 am:

       15 3 * *	1-5 find $HOME -name core 2>/dev/null |	xargs rm -f

       Example 2: Mailing a birthday greeting

       0 12 14 2 * mailx john%Happy Birthday!%Time for lunch.

       Example 3: Specifying days of the month and week

       This example

       0 0 1,15	* 1
       would  run  a command on	the first and fifteenth	of each	month, as well
       as on every Monday.

       To specify days by only one field, the other field should be set	to  *.
       For example:

       0 0 * * 1
       would run a command only	on Mondays.

ENVIRONMENT VARIABLES
       See  environ(5) for descriptions	of the following environment variables
       that  affect  the  execution  of	 crontab:  LC_TYPE,  LC_MESSAGES,  and
       NLSPATH.

       EDITOR
	     Determine	the  editor to be invoked when the -e option is	speci-
	     fied.  The	default	editor is ed(1). If both the EDITOR and	VISUAL
	     environment  variables  are set, the value	of the VISUAL variable
	     is	selected as the	editor.

EXIT STATUS
       The following exit values are returned:

       0     Successful	completion.

       >0    An	error occurred.

FILES
       /etc/cron.d
	     main cron directory

       /etc/cron.d/cron.allow
	     list of allowed users

       /etc/default/cron
	     contains cron default settings

       /etc/cron.d/cron.deny
	     list of denied users

       /var/cron/log
	     accounting	information

       /var/spool/cron/crontabs
	     spool area	for crontab

ATTRIBUTES
       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE	TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Availability		     |SUNWcsu			   |
       +-----------------------------+-----------------------------+

SEE ALSO
       atq(1),	 atrm(1),   auths(1),	ed(1),	 sh(1),	  cron(1M),    su(1M),
       auth_attr(4), attributes(5), environ(5)

NOTES
       If  you inadvertently enter the crontab command with no argument(s), do
       not attempt to get out with Control-d. This removes all entries in your
       crontab file. Instead, exit with	Control-c.

       If  an  authorized user modifies	another	user's crontab file, resulting
       behavior	may be unpredictable. Instead, the super-user should first use
       su(1M) to become	super-user to the other	user's login before making any
       changes to the crontab file.

       When updating cron, check first for existing crontab entries  that  may
       be  scheduled close to the time of the update. Such entries may be lost
       if the update process completes after the  scheduled  event.  This  can
       happen because, when cron is notified by	crontab	to update the internal
       view of a user's	crontab	file, it first	removes	 the  user's  existing
       internal	 crontab  and any internal scheduled events. Then it reads the
       new crontab file	and rebuilds the internal  crontab  and	 events.  This
       last  step  takes  time,	 especially with a large crontab file, and may
       complete	after an existing crontab entry	is scheduled to	run if	it  is
       scheduled too close to the update. To be	safe, start a new job at least
       60 seconds after	the current date and time.

SunOS 5.9			  3 Dec	2001			    crontab(1)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXAMPLES | ENVIRONMENT VARIABLES | EXIT STATUS | FILES | ATTRIBUTES | SEE ALSO | NOTES

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