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rc3(8) [osf1 man page]

rc3(8)							      System Manager's Manual							    rc3(8)

NAME
rc3 - Run command script executed when entering a multiuser run level SYNOPSIS
rc3 DESCRIPTION
The rc3 script contains run commands that enable initialization of the system to a multiuser state; run level 3. In addition to commands listed within the script itself, rc3 contains instructions to run certain commands found in the /sbin/rc3.d directory. The script defines the conditions under which the commands execute; some commands run if the system is booting, other commands execute if the system is chang- ing run levels. By convention, files in the rc3.d directory begin with either the letter "S" or the letter "K" and are followed by a two-digit number and a filename; for example: S00inet S55inetd S70mount S65lpd In general, the system starts commands that begin with the letter "S" and stops commands that begin with the letter "K." Commands that begin with the letter "K" run only when the system is changing run levels from a higher to a lower level. Commands that begin with the letter "S" run in all cases. The numbering of commands in the /sbin/rc3.d directory is important since the numbers are sorted and the com- mands are run in ascending order. Files in the /sbin/rc3.d directory are normally links to files in the /etc/init.d directory. An entry in the inittab file causes the system to execute the rc3 run commands, for example: s3:3:wait:/sbin/rc3 < /dev/console > /dev/con- sole 2>&1 The following operations are typical of those that result from executing the rc3 script and the commands located in the /sbin/rc3.d direc- tory. The operation depends on which state the system is entering or exiting. Setting the time zone Checking the current run level Start- ing network services and daemons Starting (or stopping) system services and daemons Mounting file systems Setting the TIMEZONE variable is one of the first operations completed by the rc3 script. This action provides the default time zone for subsequent commands. FILES
Specifies the command path Specifies the directory of commands that correspond to the run level RELATED INFORMATION
Commands: init(8), rc0(8), rc2(8) delim off rc3(8)

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cron(8) 						      System Manager's Manual							   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. 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 command creates a log of its activities. The cron daemon must be started from the system startup scripts because it must begin execution without a login user ID set. 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 It also establishes the following attributes from the authentication profile of the account associated with the login user ID of the invok- ing process: Audit control and disposition masks Kernel authorizations 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
Specifies the command path. Main cron directory Directory containing the crontab files. List of allowed users. List of denied users His- tory information for cron Queue description file for at, batch, and cron RELATED INFORMATION
Commands: at(1), crontab(1), rc0(8), rc2(8), rc3(8) Files: queuedefs(4) delim off cron(8)
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