1CRON(8)                     System Manager's Manual                    CRON(8)
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NAME

6       cron - clock daemon
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SYNOPSIS

9       /etc/cron
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DESCRIPTION

12       Cron  executes  commands  at specified dates and times according to the
13       instructions in the file /usr/lib/crontab.  Since cron never exits,  it
14       should  only  be executed once.  This is best done by running cron from
15       the initialization process through the file /etc/rc; see init(8).
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17       Crontab consists of lines of six fields each.  The fields are separated
18       by  spaces or tabs.  The first five are integer patterns to specify the
19       minute (0-59), hour (0-23), day of the month (1-31), month of the  year
20       (1-12),  and  day  of the week (1-7 with 1=monday).  Each of these pat‐
21       terns may contain a number in the range above; two numbers separated by
22       a  minus meaning a range inclusive; a list of numbers separated by com‐
23       mas meaning any of the numbers; or an asterisk meaning all  legal  val‐
24       ues.   The sixth field is a string that is executed by the Shell at the
25       specified times.  A percent character in this field is translated to  a
26       new-line  character.  Only the first line (up to a % or end of line) of
27       the command field is executed by the Shell.  The other lines  are  made
28       available to the command as standard input.
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30       Crontab is examined by cron every minute.
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FILES

33       /usr/lib/crontab
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37                                                                       CRON(8)
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