sd_event_source_set_description
systemd
More text
Zbigniew
Jędrzejewski-Szmek
zbyszek@in.waw.pl
sd_event_source_set_description
3
sd_event_source_set_description
sd_event_source_get_description
Set or retrieve descriptive names of event sources
#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-event3
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_signal3,
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.
See Also
sd-event3,
sd_event_add_io3,
sd_event_add_time3,
sd_event_add_child3,
sd_event_add_signal3,
sd_event_add_defer3,
sd_event_source_set_userdata3