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cron(8)
NAME
  cron - The system clock daemon

SYNOPSIS
  /usr/sbin/cron

DESCRIPTION
  The cron daemon runs shell commands at specified dates and times.  Commands
  that are to run according to a regular or periodic schedule are found
  within the crontab files. Commands that are to run once only are found
  within the at files.	You submit crontab and at file entries by using the
  crontab and at commands.  Because the cron process exits only when killed
  or when the system stops, only one cron daemon should exist on the system
  at any given time.  Normally, you start the cron daemon from within a run
  command file.

				     Note

       Other that logging a startup entry in the /var/adm/cron/log file, the
       cron daemon does not log its activities.	 You can use the Event
       Manager (EVM) to create custom events for tasks that are scheduled by
       the cron daemon. See EVM(5) for more information.

  During process initialization and when cron detects a change, it examines
  the crontab and at files. This strategy reduces the overhead of checking
  for new or changed files at regularly scheduled intervals. The cron daemon
  must be started from the system startup scripts because it must begin
  execution without a login user ID set. It maintains the /usr/spool
  cron/atjobs and the /usr spool cron/crontabs spool direcitories as
  multilevel directories; jobs and crontabs submitted reside in the directory
  associated with the sensitivity level of the process that invoked at or
  crontab. It uses the level of the subdirectory as the one at which to start
  the job.  The cron communication FIFO is graded at the System High
  sensitivity level. The cron daemon starts each job with the following
  process attributes stored with the job by the invoking process:

    ·  Login user ID

    ·  Effective and real user IDs

    ·  Effective and real group IDs

    ·  Supplementary groups

    ·  Sensitivity level

    ·  Information label

  It also establishes the following attributes from the authentication
  profile of the account associated with the login user ID of the invoking
  process:

    ·  Audit control and disposition masks

    ·  Clearance

    ·  Kernel authorizations

    ·  Base privilege set

DIAGNOSTICS
  The at and batch programs will refuse to accept jobs submitted from
  processes whose login user ID is different from the real user ID.

FILES
  /usr/sbin/cron
      Specifies the command path.

  /var/adm/cron
      Main cron directory

  /var/spool/cron/crontabs
      Directory containing the crontab files.

  /var/adm/cron/cron.allow
      List of allowed users.

  /var/adm/cron/cron.deny
      List of denied users

  /var/adm/cron/log
      This file contains startup information. (It is not a log of cron
      activities).

  /var/adm/cron/queuedefs
      Queue description file for at, batch, and cron

SEE ALSO
  Commands: at(1), crontab(1), rc0(8), rc2(8), rc3(8)

  Files: queuedefs(4)

  Misc: EVM(5)

Index for Section 8

Alphabetical listing for C

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