Chapter 9. The Operating System

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in your script.

  When the configuration is reloaded

When a daemon is forced to reload its configuration files you should use the following

format:

Reloading

description

configuration...done.

where description is the same as in the daemon starting message.

9.5 Cron jobs

Packages must not modify the configuration file

/etc/crontab

, and they must not modify

the files in

/var/spool/cron/crontabs

.

If a package wants to install a job that has to be executed via cron, it should place a file with

the name of the package in one or more of the following directories:

/etc/cron.daily

/etc/cron.weekly

/etc/cron.monthly

As these directory names imply, the files within them are executed on a daily, weekly, or

monthly basis, respectively. The exact times are listed in

/etc/crontab

.

All files installed in any of these directories must be scripts (e.g., shell scripts or Perl scripts) so

that they can easily be modified by the local system administrator. In addition, they should be

treated as configuration files.

If a certain job has to be executed more frequently than daily, the package should install a file

/etc/cron.d/

package

. This file uses the same syntax as

/etc/crontab

and is processed

by

cron

automatically. The file must also be treated as a configuration file. (Note that entries

in the

/etc/cron.d

directory are not handled by

anacron

. Thus, you should only use this

directory for jobs which may be skipped if the system is not running.)

The scripts or crontab entries in these directories should check if all necessary programs are

installed before they try to execute them. Otherwise, problems will arise when a package was

removed but not purged since configuration files are kept on the system in this situation.

9.6 Menus

The Debian

menu

package provides a standard interface between packages providing appli 

cations and menu programs (either X window managers or text based menu programs such as

pdmenu

).

All packages that provide applications that need not be passed any special command line argu 

ments for normal operation should register a menu entry for those applications, so that users