diff options
| author | Lennart Poettering <lennart@poettering.net> | 2015-01-06 00:26:25 +0100 |
|---|---|---|
| committer | Lennart Poettering <lennart@poettering.net> | 2015-01-06 03:16:39 +0100 |
| commit | a354329f724d6ce913d2ccffb2be8f3327a67faa (patch) | |
| tree | b6b05cc2c42c274f8385a16b1896d6c88bf4fc8f /man/systemd.service.xml | |
| parent | 75399049653f2d5e22032da70cf96f20d7b4d9a6 (diff) | |
core: add new logic for services to store file descriptors in PID 1
With this change it is possible to send file descriptors to PID 1, via
sd_pid_notify_with_fds() which PID 1 will store individually for each
service, and pass via the usual fd passing logic on next invocation.
This is useful for enable daemon reload schemes where daemons serialize
their state to /run, push their fds into PID 1 and terminate, restoring
their state on next start from the data in /run and passed in from PID
1.
The fds are kept by PID 1 as long as no POLLHUP or POLLERR is seen on
them, and the service they belong to are either not dead or failed, or
have a job queued.
Diffstat (limited to 'man/systemd.service.xml')
| -rw-r--r-- | man/systemd.service.xml | 29 |
1 files changed, 29 insertions, 0 deletions
diff --git a/man/systemd.service.xml b/man/systemd.service.xml index 0b68aa0890..4c890dfb7b 100644 --- a/man/systemd.service.xml +++ b/man/systemd.service.xml @@ -1117,6 +1117,35 @@ command.</para></listitem> </varlistentry> + <varlistentry> + <term><varname>FileDescriptorStoreMax=</varname></term> + <listitem><para>Configure how many + file descriptors may be stored in the + service manager for the service using + <citerefentry><refentrytitle>sd_pid_notify_with_fds</refentrytitle><manvolnum>3</manvolnum></citerefentry>'s + <literal>FDSTORE=1</literal> + messages. This is useful for + implementing service restart schemes + where the state is serialized to + <filename>/run</filename> and the file + descriptors passed to the service + manager, to allow restarts without + losing state. Defaults to 0, i.e. no + file descriptors may be stored in the + service manager by default. All file + descriptors passed to the service + manager from a specific service are + passed back to the service's main + process on the next service + restart. Any file descriptors passed + to the service manager are + automatically closed when POLLHUP or + POLLERR is seen on them, or when the + service is fully stopped and no job + queued or being executed for + it.</para></listitem> + </varlistentry> + </variablelist> <para>Check |