diff options
Diffstat (limited to 'upstream/opensuse-leap-15-6/man1/crontab.1')
| -rw-r--r-- | upstream/opensuse-leap-15-6/man1/crontab.1 | 251 |
1 files changed, 251 insertions, 0 deletions
diff --git a/upstream/opensuse-leap-15-6/man1/crontab.1 b/upstream/opensuse-leap-15-6/man1/crontab.1 new file mode 100644 index 00000000..d080ceff --- /dev/null +++ b/upstream/opensuse-leap-15-6/man1/crontab.1 @@ -0,0 +1,251 @@ +.\"/* Copyright 1988,1990,1993 by Paul Vixie +.\" * All rights reserved +.\" */ +.\" +.\" Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC") +.\" Copyright (c) 1997,2000 by Internet Software Consortium, Inc. +.\" +.\" Permission to use, copy, modify, and distribute this software for any +.\" purpose with or without fee is hereby granted, provided that the above +.\" copyright notice and this permission notice appear in all copies. +.\" +.\" THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES +.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF +.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR +.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES +.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN +.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT +.\" OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. +.\" +.\" Modified 2010/09/12 by Colin Dean, Durham University IT Service, +.\" to add clustering support. +.\" +.\" $Id: crontab.1,v 1.7 2004/01/23 19:03:32 vixie Exp $ +.\" +.TH CRONTAB 1 "2019-10-29" "cronie" "User Commands" +.SH NAME +crontab \- maintains crontab files for individual users +.SH SYNOPSIS +.B crontab +.RB [ -u +.IR user ] +.RI < "file" +.RB | \ - > +.br +.B crontab +.RB [ -T ] +.RI < "file" +.RB | \ - > +.br +.B crontab +.RB [ -u +.IR user ] +.RB < -l " | " -r " | " -e >\ [ -i ] +.RB [ -s ] +.br +.B crontab +.BR -n \ [ +.IR "hostname " ] +.br +.B crontab +.BR -c +.br +.B crontab +.BR -V +.SH DESCRIPTION +.I Crontab +is the program used to install a crontab table +.IR file , +remove or list the existing tables used to serve the +.BR cron (8) +daemon. Each user can have their own crontab, and though these are files +in +.IR /var/spool/ , +they are not intended to be edited directly. For SELinux in MLS mode, +you can define more crontabs for each range. For more information, see +.BR selinux (8). +.PP +In this version of +.IR Cron +it is possible to use a network-mounted shared +.I /var/spool/cron +across a cluster of hosts and specify that only one of the hosts should +run the crontab jobs in the particular directory at any one time. You +may also use +.BR crontab +from any of these hosts to edit the same shared set of crontab files, and +to set and query which host should run the crontab jobs. +.PP +Scheduling cron jobs with +.BR crontab +can be allowed or disallowed for different users. For this purpose, use the +.I cron.allow +and +.I cron.deny +files. If the +.I cron.allow +file exists, a user must be listed in it to be allowed to use +.BR crontab . +If the +.I cron.allow +file does not exist but the +.I cron.deny +file does exist, then a user must +.I not +be listed in the +.I cron.deny +file in order to use +.BR crontab. +If neither of these files exist, then only the super user is allowed to use +.BR crontab . +.PP +Another way to restrict the scheduling of cron jobs beyond +.BR crontab +is to use PAM authentication in +.I /etc/security/access.conf +to set up users, which are allowed or disallowed to use +.BR crontab +or modify system cron jobs in the +.IR /etc/cron.d/ +directory. +.PP +The temporary directory can be set in an environment variable. If it is +not set by the user, the +.I /tmp +directory is used. +.PP +When listing a crontab on a terminal the output will be colorized unless +an environment variable +.I NO_COLOR +is set. +.PP +.SH "OPTIONS" +.TP +.B "\-u" +Specifies the name of the user whose crontab is to be modified. If this +option is not used, +.BR crontab +examines "your" crontab, i.e., the crontab of the person executing the +command. If no crontab exists for a particular user, it is created for +them the first time the +.B crontab -u +command is used under their username. +.TP +.B "\-T" +Test the crontab file syntax without installing it. +Once an issue is found, the validation is interrupted, so this will not return all the existing issues at the same execution. +.TP +.B "\-l" +Displays the current crontab on standard output. +.TP +.B "\-r" +Removes the current crontab. +.TP +.B "\-e" +Edits the current crontab using the editor specified by the +.I VISUAL +or +.I EDITOR +environment variables. After you exit from the editor, the modified +crontab will be installed automatically. +.TP +.B "\-i" +This option modifies the +.B "\-r" +option to prompt the user for a 'y/Y' response before actually removing +the crontab. +.TP +.B "\-s" +Appends the current SELinux security context string as an MLS_LEVEL +setting to the crontab file before editing / replacement occurs - see the +documentation of MLS_LEVEL in +.BR crontab (5). +.TP +.B "\-n" +This option is relevant only if +.BR cron (8) +was started with the +.B \-c +option, to enable clustering support. It is used to set the host in the +cluster which should run the jobs specified in the crontab files in the +.I /var/spool/cron +directory. If a hostname is supplied, the host whose hostname returned +by +.BR gethostname (2) +matches the supplied hostname, will be selected to run the selected cron jobs subsequently. If there +is no host in the cluster matching the supplied hostname, or you explicitly specify +an empty hostname, then the selected jobs will not be run at all. If the hostname +is omitted, the name of the local host returned by +.BR gethostname (2) +is used. Using this option has no effect on the +.I /etc/crontab +file and the files in the +.I /etc/cron.d +directory, which are always run, and considered host-specific. For more +information on clustering support, see +.BR cron (8). +.TP +.B "\-c" +This option is only relevant if +.BR cron (8) +was started with the +.B \-c +option, to enable clustering support. It is used to query which host in +the cluster is currently set to run the jobs specified in the crontab +files in the directory +.I /var/spool/cron +, as set using the +.B \-n +option. +.TP +.B "\-V" +Print version and exit. +.SH CAVEATS +The files +.I cron.allow +and +.I cron.deny +cannot be used to restrict the execution of cron jobs; they only restrict the +use of +.BR crontab . +In particular, restricting access to +.BR crontab +has no effect on an existing +.I crontab +of a user. Its jobs will continue to be executed until the crontab is removed. +.PP +The files +.I cron.allow +and +.I cron.deny +must be readable by the user invoking +.BR crontab . +If this is not the case, then they are treated as non-existent. +.SH "SEE ALSO" +.BR crontab (5), +.BR cron (8) +.SH FILES +.nf +/etc/cron.allow +/etc/cron.deny +.fi +.SH STANDARDS +The +.I crontab +command conforms to IEEE Std1003.2-1992 (``POSIX'') with one exception: +For replacing the current crontab with data from standard input the +.B \- +has to be specified on the command line if the standard input is a TTY. +This new command syntax differs from previous versions of Vixie Cron, +as well as from the classic SVR3 syntax. +.SH DIAGNOSTICS +An informative usage message appears if you run a crontab with a faulty +command defined in it. +.SH AUTHOR +.MT vixie@isc.org +Paul Vixie +.ME +.br +.MT colin@colin-dean.org +Colin Dean +.ME |