cron --
execute commands scheduled by at, batch, and crontab
Syntax
/etc/cron
Description
The cron command is the clock daemon that
executes commands at specified dates and times.
cron
processes jobs submitted with
at(C),
batch(C),
and
crontab(C).
cron never exits; the cron command usually appears in the
/etc/rc2 scripts to be invoked by
init(M)
when the system is brought up in multiuser mode.
The variable MAXCRON, if set in /etc/default/cron,
controls the maximum number of running processes that cron
can own at any one time. The default value is 100.
Diagnostics
A history of all actions by cron can be recorded in
/usr/lib/cron/log. This logging occurs only if the variable
CRONLOG is set to YES in /etc/default/cron.
By default this value is set to NO and no logging occurs.
If logging is turned on, you can use
the variable MAXLOGSIZE defined in
/etc/default/cron to limit the size in 512-byte blocks
to which the log file will grow. If it exceeds this limit, its contents
are moved to /usr/lib/cron/olog.
The default value of MAXLOGSIZE is 2048 blocks.
Limitations
cron will set the supplemental group list to that of the
user requesting the job.