NAME

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

SYNOPSIS

       #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

       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

       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.

   Errors
       Returned errors may indicate the following problems:

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

       -ENOMEM
           Not enough memory to copy the name.

       -ECHILD
           The event loop has been created in a different process.

       -ENXIO
           No name was set for the event source.

NOTES

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

SEE ALSO

       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), sd_event_source_set_userdata(3)

systemd 245                                                                   SD_EVENT_SOURCE_SET_DESCRIPTION(3)