chiark / gitweb /
man: wording and grammar update
[elogind.git] / man / systemd.exec.xml
index 71472b4f5dd308f1b6ee8fc18fdb656beab44733..c9958340afd06e242f67d14d0f1a488b248de4fe 100644 (file)
         </refnamediv>
 
         <refsynopsisdiv>
-                <para><filename>systemd.service</filename>,
-                <filename>systemd.socket</filename>,
-                <filename>systemd.mount</filename>,
-                <filename>systemd.swap</filename></para>
+                <para><filename><replaceable>service</replaceable>.service</filename>,
+                <filename><replaceable>socket</replaceable>.socket</filename>,
+                <filename><replaceable>mount</replaceable>.mount</filename>,
+                <filename><replaceable>swap</replaceable>.swap</filename></para>
         </refsynopsisdiv>
 
         <refsect1>
@@ -69,7 +69,7 @@
                 files, and
                 <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
                 <citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
-                <citerefentry><refentrytitle>systemd.swap</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+                <citerefentry><refentrytitle>systemd.swap</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
                 and
                 <citerefentry><refentrytitle>systemd.mount</refentrytitle><manvolnum>5</manvolnum></citerefentry>
                 for more information on the specific unit
@@ -82,7 +82,7 @@
         <refsect1>
                 <title>Options</title>
 
-                <variablelist>
+                <variablelist class='unit-directives'>
 
                         <varlistentry>
                                 <term><varname>WorkingDirectory=</varname></term>
 
                                 <listitem><para>Sets the supplementary
                                 Unix groups the processes are executed
-                                as. This takes a space separated list
+                                as. This takes a space-separated list
                                 of group names or IDs. This option may
                                 be specified more than once in which
                                 case all listed groups are set as
                                 empty string is assigned to this
                                 option the list of environment
                                 variables is reset, all prior
-                                assignments have no effect. See
+                                assignments have no effect.
+                                Variable expansion is not performed
+                                inside the strings, however, specifier
+                                expansion is possible. $ character has
+                                no special meaning.
+                                If you need to assign a value containing spaces
+                                to a variable, use double quotes (")
+                                for the assignment.</para>
+
+                                <para>Example:
+                                <programlisting>Environment="VAR1=word1 word2" VAR2=word3 "VAR3=word 5 6"</programlisting>
+                                gives three variables <literal>VAR1</literal>,
+                                <literal>VAR2</literal>, <literal>VAR3</literal>.
+                                </para>
+
+                                <para>
+                                See
                                 <citerefentry><refentrytitle>environ</refentrytitle><manvolnum>7</manvolnum></citerefentry>
-                                for details.</para></listitem>
+                                for details about environment variables.</para></listitem>
                         </varlistentry>
                         <varlistentry>
                                 <term><varname>EnvironmentFile=</varname></term>
                                 <varname>Environment=</varname> but
                                 reads the environment variables from a
                                 text file. The text file should
-                                contain new-line separated variable
+                                contain new-line-separated variable
                                 assignments. Empty lines and lines
                                 starting with ; or # will be ignored,
-                                which may be used for commenting. The
-                                parser strips leading and
-                                trailing whitespace from the values
+                                which may be used for commenting. A line
+                                ending with a backslash will be concatenated
+                                with the following one, allowing multiline variable
+                                definitions. The parser strips leading
+                                and trailing whitespace from the values
                                 of assignments, unless you use
                                 double quotes (").</para>
 
                                 <para>The argument passed should be an
-                                absolute file name or wildcard
+                                absolute filename or wildcard
                                 expression, optionally prefixed with
-                                "-", which indicates that if the file
-                                does not exist it won't be read and no
-                                error or warning message is logged.
-                                This option may be specified more than
-                                once in which case all specified files
-                                are read. If the empty string is
-                                assigned to this option the list of
-                                file to read is reset, all prior
-                                assignments have no effect.</para>
+                                <literal>-</literal>, which indicates
+                                that if the file does not exist it
+                                won't be read and no error or warning
+                                message is logged.  This option may be
+                                specified more than once in which case
+                                all specified files are read. If the
+                                empty string is assigned to this
+                                option the list of file to read is
+                                reset, all prior assignments have no
+                                effect.</para>
 
                                 <para>The files listed with this
                                 directive will be read shortly before
                                 with
                                 <option>DefaultStandardOutput=</option>
                                 in
-                                <citerefentry><refentrytitle>systemd.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+                                <citerefentry><refentrytitle>systemd-system.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
                                 which defaults to
                                 <option>journal</option>.</para></listitem>
                         </varlistentry>
                                 setting defaults to the value set with
                                 <option>DefaultStandardError=</option>
                                 in
-                                <citerefentry><refentrytitle>systemd.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+                                <citerefentry><refentrytitle>systemd-system.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
                                 which defaults to
                                 <option>inherit</option>.</para></listitem>
                         </varlistentry>
                                 capability bounding set for the
                                 executed process. See
                                 <citerefentry><refentrytitle>capabilities</refentrytitle><manvolnum>7</manvolnum></citerefentry>
-                                for details. Takes a whitespace
-                                separated list of capability names as
-                                read by
-                                <citerefentry><refentrytitle>cap_from_name</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
+                                for details. Takes a whitespace-separated
+                                list of capability names as read by
+                                <citerefentry><refentrytitle>cap_from_name</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+                                e.g. <constant>CAP_SYS_ADMIN</constant>,
+                                <constant>CAP_DAC_OVERRIDE</constant>,
+                                <constant>CAP_SYS_PTRACE</constant>.
                                 Capabilities listed will be included
                                 in the bounding set, all others are
                                 removed. If the list of capabilities
-                                is prefixed with ~ all but the listed
-                                capabilities will be included, the
-                                effect of the assignment
-                                inverted. Note that this option also
-                                effects the respective capabilities in
-                                the effective, permitted and
-                                inheritable capability sets, on top of
-                                what <varname>Capabilities=</varname>
+                                is prefixed with <literal>~</literal>
+                                all but the listed capabilities will
+                                be included, the effect of the
+                                assignment inverted. Note that this
+                                option also affects the respective
+                                capabilities in the effective,
+                                permitted and inheritable capability
+                                sets, on top of what
+                                <varname>Capabilities=</varname>
                                 does. If this option is not used the
                                 capability bounding set is not
                                 modified on process execution, hence
                                 no limits on the capabilities of the
                                 process are enforced. This option may
                                 appear more than once in which case
-                                the bounding sets are merged. If the empty
-                                string is assigned to this option the
-                                bounding set is reset, and all prior
-                                settings have no
-                                effect.</para></listitem>
+                                the bounding sets are merged. If the
+                                empty string is assigned to this
+                                option the bounding set is reset to
+                                the empty capability set, and all
+                                prior settings have no effect. If set
+                                to <literal>~</literal> (without any
+                                further argument) the bounding set is
+                                reset to the full set of available
+                                capabilities, also undoing any
+                                previous settings.</para></listitem>
                         </varlistentry>
 
                         <varlistentry>
                                 space-separated list of cgroup
                                 identifiers. A cgroup identifier is
                                 formatted like
-                                <filename>cpu:/foo/bar</filename>,
+                                <filename noindex='true'>cpu:/foo/bar</filename>,
                                 where "cpu" indicates the kernel
                                 control group controller used, and
-                                <filename>/foo/bar</filename> is the
+                                <filename noindex='true'>/foo/bar</filename> is the
                                 control group path. The controller
                                 name and ":" may be omitted in which
                                 case the named systemd control group
                                 in specific paths in specific kernel
                                 controller hierarchies. It is not
                                 recommended to manipulate the service
-                                control group path in the systemd
-                                named hierarchy. For details about
+                                control group path in the private
+                                systemd named hierarchy
+                                (i.e. <literal>name=systemd</literal>),
+                                and doing this might result in
+                                undefined behaviour. For details about
                                 control groups see <ulink
                                 url="http://www.kernel.org/doc/Documentation/cgroups/cgroups.txt">cgroups.txt</ulink>.</para>
 
                                 settings of
                                 <varname>DefaultControllers=</varname>
                                 of
-                                <citerefentry><refentrytitle>systemd.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+                                <citerefentry><refentrytitle>systemd-system.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
                                 but a unit's
                                 <varname>ControlGroup=</varname>
                                 setting for a specific controller
                                 </para></listitem>
                         </varlistentry>
 
-                        <varlistentry>
-                                <term><varname>CPUShares=</varname></term>
-
-                                <listitem><para>Assign the specified
-                                overall CPU time shares to the
-                                processes executed. Takes an integer
-                                value. This controls the
-                                <literal>cpu.shares</literal> control
-                                group attribute, which defaults to
-                                1024. For details about this control
-                                group attribute see <ulink
-                                url="http://www.kernel.org/doc/Documentation/scheduler/sched-design-CFS.txt">sched-design-CFS.txt</ulink>.</para></listitem>
-                        </varlistentry>
-
-                        <varlistentry>
-                                <term><varname>MemoryLimit=</varname></term>
-                                <term><varname>MemorySoftLimit=</varname></term>
-
-                                <listitem><para>Limit the overall memory usage
-                                of the executed processes to a certain
-                                size. Takes a memory size in bytes. If
-                                the value is suffixed with K, M, G or
-                                T the specified memory size is parsed
-                                as Kilobytes, Megabytes, Gigabytes,
-                                or Terabytes (to the base
-                                1024), respectively. This controls the
-                                <literal>memory.limit_in_bytes</literal>
-                                and
-                                <literal>memory.soft_limit_in_bytes</literal>
-                                control group attributes. For details
-                                about these control group attributes
-                                see <ulink
-                                url="http://www.kernel.org/doc/Documentation/cgroups/memory.txt">memory.txt</ulink>.</para></listitem>
-                        </varlistentry>
-
-                        <varlistentry>
-                                <term><varname>DeviceAllow=</varname></term>
-                                <term><varname>DeviceDeny=</varname></term>
-
-                                <listitem><para>Control access to
-                                specific device nodes by the executed processes. Takes two
-                                space separated strings: a device node
-                                path (such as
-                                <filename>/dev/null</filename>)
-                                followed by a combination of r, w, m
-                                to control reading, writing, or
-                                creating of the specific device node
-                                by the unit, respectively. This controls the
-                                <literal>devices.allow</literal>
-                                and
-                                <literal>devices.deny</literal>
-                                control group attributes. For details
-                                about these control group attributes
-                                see <ulink
-                                url="http://www.kernel.org/doc/Documentation/cgroups/devices.txt">devices.txt</ulink>.</para></listitem>
-                        </varlistentry>
-
-                        <varlistentry>
-                                <term><varname>BlockIOWeight=</varname></term>
-
-                                <listitem><para>Set the default or
-                                per-device overall block IO weight
-                                value for the executed
-                                processes. Takes either a single
-                                weight value (between 10 and 1000) to
-                                set the default block IO weight, or a
-                                space separated pair of a file path
-                                and a weight value to specify the
-                                device specific weight value (Example:
-                                "/dev/sda 500"). The file path may be
-                                specified as path to a block device
-                                node or as any other file in which
-                                case the backing block device of the
-                                file system of the file is
-                                determined. This controls the
-                                <literal>blkio.weight</literal> and
-                                <literal>blkio.weight_device</literal>
-                                control group attributes, which
-                                default to 1000. Use this option
-                                multiple times to set weights for
-                                multiple devices. For details about
-                                these control group attributes see
-                                <ulink
-                                url="http://www.kernel.org/doc/Documentation/cgroups/blkio-controller.txt">blkio-controller.txt</ulink>.</para></listitem>
-                        </varlistentry>
-
-                        <varlistentry>
-                                <term><varname>BlockIOReadBandwidth=</varname></term>
-                                <term><varname>BlockIOWriteBandwidth=</varname></term>
-
-                                <listitem><para>Set the per-device
-                                overall block IO bandwidth limit for
-                                the executed processes. Takes a space
-                                separated pair of a file path and a
-                                bandwidth value (in bytes per second)
-                                to specify the device specific
-                                bandwidth. The file path may be
-                                specified as path to a block device
-                                node or as any other file in which
-                                case the backing block device of the
-                                file system of the file is determined.
-                                If the bandwidth is suffixed with K, M,
-                                G, or T the specified bandwidth is
-                                parsed as Kilobytes, Megabytes,
-                                Gigabytes, or Terabytes, respectively (Example:
-                                "/dev/disk/by-path/pci-0000:00:1f.2-scsi-0:0:0:0
-                                5M"). This controls the
-                                <literal>blkio.read_bps_device</literal>
-                                and
-                                <literal>blkio.write_bps_device</literal>
-                                control group attributes. Use this
-                                option multiple times to set bandwidth
-                                limits for multiple devices. For
-                                details about these control group
-                                attributes see <ulink
-                                url="http://www.kernel.org/doc/Documentation/cgroups/blkio-controller.txt">blkio-controller.txt</ulink>.</para></listitem>
-                        </varlistentry>
-
                         <varlistentry>
                                 <term><varname>ReadWriteDirectories=</varname></term>
                                 <term><varname>ReadOnlyDirectories=</varname></term>
                                 <term><varname>InaccessibleDirectories=</varname></term>
 
                                 <listitem><para>Sets up a new
-                                file-system name space for executed
+                                file system namespace for executed
                                 processes. These options may be used
                                 to limit access a process might have
-                                to the main file-system
+                                to the main file system
                                 hierarchy. Each setting takes a
                                 space-separated list of absolute
                                 directory paths. Directories listed in
                                 <listitem><para>Takes a boolean
                                 argument. If true sets up a new file
                                 system namespace for the executed
-                                processes and mounts a private
-                                <filename>/tmp</filename> directory
-                                inside it, that is not shared by
+                                processes and mounts private
+                                <filename>/tmp</filename> and
+                                <filename>/var/tmp</filename> directories
+                                inside it, that are not shared by
                                 processes outside of the
                                 namespace. This is useful to secure
                                 access to temporary files of the
                                 process, but makes sharing between
                                 processes via
-                                <filename>/tmp</filename>
-                                impossible. Defaults to
+                                <filename>/tmp</filename> or
+                                <filename>/var/tmp</filename>
+                                impossible. All temporary data created
+                                by service will be removed after service
+                                is stopped. Defaults to
                                 false.</para></listitem>
                         </varlistentry>
 
                                 <term><varname>IgnoreSIGPIPE=</varname></term>
 
                                 <listitem><para>Takes a boolean
-                                argument. If true causes SIGPIPE to be
+                                argument. If true, causes <constant>SIGPIPE</constant> to be
                                 ignored in the executed
-                                process. Defaults to true, since
-                                SIGPIPE generally is useful only in
+                                process. Defaults to true because
+                                <constant>SIGPIPE</constant> generally is useful only in
                                 shell pipelines.</para></listitem>
                         </varlistentry>
 
                                 <term><varname>NoNewPrivileges=</varname></term>
 
                                 <listitem><para>Takes a boolean
-                                argument. If true ensures that the
+                                argument. If true, ensures that the
                                 service process and all its children
                                 can never gain new privileges. This
                                 option is more powerful than the respective
                         <varlistentry>
                                 <term><varname>SystemCallFilter=</varname></term>
 
-                                <listitem><para>Takes a space
-                                separated list of system call
-                                names. If this setting is used all
+                                <listitem><para>Takes a space-separated
+                                list of system call
+                                names. If this setting is used, all
                                 system calls executed by the unit
                                 process except for the listed ones
                                 will result in immediate process
-                                termination with the SIGSYS signal
+                                termination with the
+                                <constant>SIGSYS</constant> signal
                                 (whitelisting). If the first character
                                 of the list is <literal>~</literal>
                                 the effect is inverted: only the