32v 1m cron
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CRON(1M) UNIX Programmer's Manual CRON(1M)
Contents
NAME
cron - clock daemon
SYNOPSIS
/etc/cron
DESCRIPTION
_C_r_o_n executes commands at specified dates and times accord-
ing to the instructions in the file /usr/lib/crontab. Since
_c_r_o_n never exits, it should only be executed once. This is
best done by running _c_r_o_n from the initialization process
through the file /etc/rc; see _i_n_i_t(8).
Crontab consists of lines of six fields each. The fields
are separated by spaces or tabs. The first five are integer
patterns to specify the minute (0-59), hour (0-23), day of
the month (1-31), month of the year (1-12), and day of the
week (1-7 with 1=monday). Each of these patterns may con-
tain a number in the range above; two numbers separated by a
minus meaning a range inclusive; a list of numbers separated
by commas meaning any of the numbers; or an asterisk meaning
all legal values. The sixth field is a string that is exe-
cuted by the Shell at the specified times. A percent char-
acter in this field is translated to a new-line character.
Only the first line (up to a % or end of line) of the com-
mand field is executed by the Shell. The other lines are
made available to the command as standard input.
Crontab is examined by _c_r_o_n every minute.
FILES
/usr/lib/crontab
