White space fix only. Translators can ignore.
Sponsored by: iXsystems
This commit is contained in:
Dru Lavigne
parent
1f1d8dbccb
commit
4e8e3f8b52
Notes:
svn2git
2020-12-08 03:00:23 +00:00
svn path=/head/; revision=44767
1 changed files with 74 additions and 79 deletions
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@ -232,30 +232,29 @@ run_rc_command "$1"</programlisting>
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<secondary>configuration</secondary>
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</indexterm>
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<para>One of the most useful utilities in &os; is <application>cron</application>.
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This utility runs in the background and regularly checks
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<para>One of the most useful utilities in &os; is
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<application>cron</application>. This utility runs in the
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background and regularly checks
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<filename>/etc/crontab</filename> for tasks to execute and
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searches <filename>/var/cron/tabs</filename> for custom
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crontab files. These files are used to schedule
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tasks which <application>cron</application> runs at the
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specified times. Each entry in a crontab defines a task to run
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and is known as a <firstterm>cron job</firstterm>.</para>
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searches <filename>/var/cron/tabs</filename> for custom crontab
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files. These files are used to schedule tasks which
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<application>cron</application> runs at the specified times.
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Each entry in a crontab defines a task to run and is known as a
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<firstterm>cron job</firstterm>.</para>
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<para>Two different types of configuration files are used:
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the system crontab, which should not be modified, and user
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crontabs, which can be created and edited as needed. The format
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used by these files is documented in &man.crontab.5;. The
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format of the system crontab, <filename>/etc/crontab</filename>
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includes a <literal>who</literal> column which does not exist in
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user crontabs. In the system crontab,
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<application>cron</application> runs the command as
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the user specified in this column. In a user
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crontab, all commands run as the user who
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created the crontab.</para>
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<para>Two different types of configuration files are used: the
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system crontab, which should not be modified, and user crontabs,
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which can be created and edited as needed. The format used by
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these files is documented in &man.crontab.5;. The format of the
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system crontab, <filename>/etc/crontab</filename> includes a
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<literal>who</literal> column which does not exist in user
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crontabs. In the system crontab,
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<application>cron</application> runs the command as the user
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specified in this column. In a user crontab, all commands run
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as the user who created the crontab.</para>
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<para>User crontabs allow
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individual users to schedule their own tasks. The <systemitem
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class="username">root</systemitem> user
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<para>User crontabs allow individual users to schedule their own
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tasks. The <systemitem class="username">root</systemitem> user
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can also have a user <filename>crontab</filename> which can be
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used to schedule tasks that do not exist in the system
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<filename>crontab</filename>.</para>
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@ -276,13 +275,12 @@ PATH=/etc:/bin:/sbin:/usr/bin:/usr/sbin <co xml:id="co-env"/>
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<calloutlist>
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<callout arearefs="co-comments">
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<para>Lines that begin
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with the <literal>#</literal> character are comments. A
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comment can be placed in the file as a reminder of what and
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why a desired action is performed. Comments cannot be on
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the same line as a command or else they will be interpreted
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as part of the command; they must be on a new line. Blank
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lines are ignored.</para>
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<para>Lines that begin with the <literal>#</literal> character
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are comments. A comment can be placed in the file as a
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reminder of what and why a desired action is performed.
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Comments cannot be on the same line as a command or else
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they will be interpreted as part of the command; they must
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be on a new line. Blank lines are ignored.</para>
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</callout>
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<callout arearefs="co-env">
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@ -290,45 +288,43 @@ PATH=/etc:/bin:/sbin:/usr/bin:/usr/sbin <co xml:id="co-env"/>
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define any environment settings. In this example, it is
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used to define the <envar>SHELL</envar> and
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<envar>PATH</envar>. If the <envar>SHELL</envar> is
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omitted, <application>cron</application> will use the default Bourne shell.
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If the <envar>PATH</envar> is omitted, the full path must be given to the
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command or script to run.</para>
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omitted, <application>cron</application> will use the
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default Bourne shell. If the <envar>PATH</envar> is
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omitted, the full path must be given to the command or
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script to run.</para>
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</callout>
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<callout arearefs="co-field-descr">
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<para>This line defines the seven fields used in a system crontab:
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<literal>minute</literal>,
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<literal>hour</literal>, <literal>mday</literal>,
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<literal>month</literal>, <literal>wday</literal>,
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<literal>who</literal>, and <literal>command</literal>.
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The
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<literal>minute</literal> field is the time in minutes when the
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specified command will be run, the <literal>hour</literal> is
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the hour when the specified command will be run, the
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<literal>mday</literal> is the day of the month,
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<literal>month</literal> is the month, and
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<literal>wday</literal> is the day of the week.
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<para>This line defines the seven fields used in a system
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crontab: <literal>minute</literal>, <literal>hour</literal>,
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<literal>mday</literal>, <literal>month</literal>,
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<literal>wday</literal>, <literal>who</literal>, and
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<literal>command</literal>. The <literal>minute</literal>
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field is the time in minutes when the specified command will
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be run, the <literal>hour</literal> is the hour when the
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specified command will be run, the <literal>mday</literal>
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is the day of the month, <literal>month</literal> is the
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month, and <literal>wday</literal> is the day of the week.
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These fields must be numeric values, representing the
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twenty-four hour clock, or a <literal>*</literal>,
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representing all values for that field. The
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<literal>who</literal> field only exists in the system
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crontab and specifies which user the command
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should be run as. The last field is the command to be
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executed.</para>
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crontab and specifies which user the command should be run
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as. The last field is the command to be executed.</para>
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</callout>
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<callout arearefs="co-main">
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<para>This entry defines the values for this cron job.
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The <literal>*/5</literal>, followed
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by several more <literal>*</literal> characters, specifies that
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<para>This entry defines the values for this cron job. The
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<literal>*/5</literal>, followed by several more
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<literal>*</literal> characters, specifies that
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<command>/usr/libexec/atrun</command> is invoked by
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<systemitem class="username">root</systemitem> every five
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minutes of every hour, of every day and day of the week, of
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every month.</para>
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<para>Commands can include any number of switches.
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However, commands which extend to multiple lines need to be
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broken with the backslash <quote>\</quote> continuation
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<para>Commands can include any number of switches. However,
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commands which extend to multiple lines need to be broken
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with the backslash <quote>\</quote> continuation
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character.</para>
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</callout>
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</calloutlist>
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@ -346,30 +342,30 @@ PATH=/etc:/bin:/sbin:/usr/bin:/usr/sbin <co xml:id="co-env"/>
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an empty file. Once a user creates a crontab, this command
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will open that file for editing.</para>
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<para>It is useful to add these lines to the top of the crontab
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file in order to set the environment variables and to remember
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the meanings of the fields in the crontab:</para>
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<programlisting>SHELL=/bin/sh
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<para>It is useful to add these lines to the top of the crontab
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file in order to set the environment variables and to remember
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the meanings of the fields in the crontab:</para>
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<programlisting>SHELL=/bin/sh
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PATH=/etc:/bin:/sbin:/usr/bin:/usr/sbin
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# Order of crontab fields
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# minute hour mday month wday command</programlisting>
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<para>Then add a line for each command or script to run,
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specifying the time to run the command. This example runs the
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specified custom Bourne shell script every day at two in the
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afternoon. Since the path to the script is not specified in
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<literal>PATH</literal>, the full path to the script is
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given:</para>
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<programlisting>0 14 * * * /usr/home/dru/bin/mycustomscript.sh</programlisting>
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<para>Then add a line for each command or script to run,
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specifying the time to run the command. This example runs the
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specified custom Bourne shell script every day at two in the
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afternoon. Since the path to the script is not specified in
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<literal>PATH</literal>, the full path to the script is
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given:</para>
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<tip>
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<para>Before using a custom script, make sure it is executable
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and test that it works as intended from the command line.
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This is especially important if the script includes any
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commands that deletes files using wildcards.</para>
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</tip>
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<programlisting>0 14 * * * /usr/home/dru/bin/mycustomscript.sh</programlisting>
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<tip>
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<para>Before using a custom script, make sure it is executable
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and test that it works as intended from the command line.
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This is especially important if the script includes any
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commands that deletes files using wildcards.</para>
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</tip>
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<para>When finished editing the crontab, save the file. It
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will automatically be installed and
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@ -381,10 +377,9 @@ PATH=/etc:/bin:/sbin:/usr/bin:/usr/sbin
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0 14 * * * /usr/home/dru/bin/mycustomscript.sh</screen>
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<para>To remove all of the cron jobs in a user crontab:</para>
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<screen>&prompt.user; <userinput>crontab -l</userinput>
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remove crontab for dru? <userinput>y</userinput></screen>
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</sect2>
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</sect1>
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@ -654,14 +649,14 @@ ifconfig_fxp0="inet 10.1.1.1/8"</programlisting>
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information about the supported hardware and any known
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limitations of the driver.</para>
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<para>The drivers for common <acronym>NIC</acronym>s are
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already present in the <filename>GENERIC</filename> kernel,
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meaning the <acronym>NIC</acronym> should be probed during boot.
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The system's boot messages can be viewed by typing
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<para>The drivers for common <acronym>NIC</acronym>s are already
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present in the <filename>GENERIC</filename> kernel, meaning
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the <acronym>NIC</acronym> should be probed during boot. The
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system's boot messages can be viewed by typing
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<command>more /var/run/dmesg.boot</command> and using the
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spacebar to scroll through the text. In this example, two
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Ethernet <acronym>NIC</acronym>s using the
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&man.dc.4; driver are present on the system:</para>
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Ethernet <acronym>NIC</acronym>s using the &man.dc.4; driver
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are present on the system:</para>
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<screen>dc0: <82c169 PNIC 10/100BaseTX> port 0xa000-0xa0ff mem 0xd3800000-0xd38
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000ff irq 15 at device 11.0 on pci0
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