sd_event_source_get_description(3) — Linux manual page



NAME         top

       sd_event_source_set_description, sd_event_source_get_description -
       Set or retrieve descriptive names of event sources

SYNOPSIS         top

       #include <systemd/sd-event.h>

       int sd_event_source_set_description(sd_event_source *source,
                                           const char *description);

       int sd_event_source_get_description(sd_event_source *source,
                                           const char **description);

DESCRIPTION         top

       sd_event_source_set_description() may be used to set an arbitrary
       descriptive name for the event source object specified as source.
       This name will be used in debugging messages generated by sd-event(3)
       for this event source, and may be queried using
       sd_event_source_get_description() for debugging purposes. The
       description parameter shall point to a NUL-terminated string or be
       NULL. In the latter case, the descriptive name will be unset. The
       string is copied internally, hence the description argument is not
       referenced after the function returns.

       sd_event_source_get_description() may be used to query the current
       descriptive name assigned to the event source object source. It
       returns a pointer to the current name in description, stored in
       memory internal to the event source. The memory is invalidated when
       the event source is destroyed or the descriptive name is changed.

       Event source objects generally have no description set when they are
       created, except for UNIX signal event sources created with
       sd_event_add_signal(3), whose descriptive name is initialized to the
       signal's C constant name (e.g.  "SIGINT" or "SIGTERM").

RETURN VALUE         top

       On success, sd_event_source_set_description() and
       sd_event_source_get_description() return a non-negative integer. On
       failure, they return a negative errno-style error code.

       Returned errors may indicate the following problems:

           source is not a valid pointer to an sd_event_source object or the
           description argument for sd_event_source_get_description() is

           Not enough memory to copy the name.

           The event loop has been created in a different process.

           No name was set for the event source.

NOTES         top

       These APIs are implemented as a shared library, which can be compiled
       and linked to with the libsystemd pkg-config(1) file.

SEE ALSO         top

       sd-event(3), sd_event_add_io(3), sd_event_add_time(3),
       sd_event_add_signal(3), sd_event_add_child(3),
       sd_event_add_inotify(3), sd_event_add_defer(3),

COLOPHON         top

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systemd 246                               SD_EVENT_SOURCE_SET_DESCRIPTION(3)

Pages that refer to this page: 30-systemd-environment-d-generator(7)systemd.index(7)