fcron - daemon to execute scheduled tasks
fcron [ -c file ] [ -d ] [ -b ] [ -s time ] [ -m num ] [ -q num ]
fcron [ -c file ] [ -d ] [ -f ] [ -o ] [ -y ] [ -l time ]
fcron [ -n dir ]
fcron [ -h ]
fcron [ -V ]
Fcron should be started from /etc/rc or /etc/rc.local. Unless the -f
(or --foreground) option is given, it will return immediately, so you
don’t need to start it with ’&’.
Fcron loads users fcrontabs (see fcrontab(5)) files previously
installed by fcrontab (see fcrontab(1)). Then, fcron calculates the
time and date of each job’s next execution, and determines how long it
has to sleep, and sleeps for this amount of time. When it wakes up, it
checks all jobs loaded and runs them if needed. When a job is executed,
fcron forks, changes its user and group permissions to match those of
the user the job is being done for, executes that job and mails the
outputs to the user (this can be changed: see fcrontab(5)).
Informative message about what fcron is doing are sent to syslogd(8)
under facility cron, priority notice. Warning and error messages are
sent respectively at priority warning and error.
Note: fcron sleeps at least 20 seconds after it has been started
before executing a job to avoid to use too much resources during
Don’t fork to the background. In this mode, fcron will output
informational message to standard error as well as to syslogd.
Force running in background, even if fcron has been compiled to
run in foreground as default.
Save fcrontabs on disk every time sec (default is 1800).
Set to num the maximum number of serial jobs which can run
simultaneously. By default, this value is set to 1.
See also: option serial in fcrontab(5).
Set to n the number of jobs the serial queue and the lavg queue
Make fcron use config file file instead of default config file
/etc/fcron.conf. To interact with that running fcron process,
fcrontab must use the same config file (which is defined by
fcrontab’s option -c). That way, several fcron processes can run
simultaneously on an only system (but each fcron process *must*
have a different spool dir and pid file from the other
--once Execute all jobs that need to be run at the time fcron was
started, wait for them, then return. Sets firstsleep to 0. May
be especially useful when used with options -y and -f in a
script run, for instance, at dialup connection.
See also: fcrontab’s options volatile, stdout.
Don’t log to syslog at all. May be useful when running in
Sets the initial delay (in seconds) before any job is executed,
default to 20 seconds.
Create dir as a new spool directory for fcron. Set correctly its
mode and owner. Then, exit.
--help Display a brief description of the options.
Display an informational message about fcron, including its
version and the license under which it is distributed.
Run in debug mode (more details on stderr -- if option -f is set
-- and in log file)
Fcron returns 0 on normal exit, and 1 on error.
Save configuration (time remaining until next execution, time
and date of next execution, etc), wait for all running jobs and
Force fcron to reload its configuration.
Make fcron print its current schedule on syslog. It also toggles
on/off the printing on debug info on syslog.
SIGHUP Tell fcron to check if there is any configuration update (this
signal is used by fcrontab(5))
Should be POSIX compliant.
Configuration file for fcron, fcrontab and fcrondyn: contains
paths (spool dir, pid file) and default programs to use (editor,
shell, etc). See fcron.conf(5) for more details.
Users allowed to use fcrontab and fcrondyn (one name per line,
special name "all" acts for everyone)
Users who are not allowed to use fcrontab and fcrondyn (same
format as allow file)
/etc/pam.d/fcron (or /etc/pam.conf)
PAM configuration file for fcron. Take a look at pam(8) for more
If you’re learning how to use fcron from scratch, I suggest that you
read the HTML version of the documentation (if your are not reading it
right now! :) ): the content is the same, but it is easier to navigate
thanks to the hyperlinks.
Thibault Godouet <email@example.com>