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NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | NOTES | SEE ALSO | COLOPHON |
SD_EVENT_SOURCE_SET_DESCRIPTION(3)urce_set_descriptionRCE_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);
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").
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:
-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.
These APIs are implemented as a shared library, which can be compiled
and linked to with the libsystemd pkg-config(1) file.
sd-event(3), sd_event_add_io(3), sd_event_add_time(3),
sd_event_add_child(3), sd_event_add_signal(3), sd_event_add_defer(3),
sd_event_source_set_userdata(3)
This page is part of the systemd (systemd system and service manager)
project. Information about the project can be found at
⟨http://www.freedesktop.org/wiki/Software/systemd⟩. If you have a bug
report for this manual page, see
⟨http://www.freedesktop.org/wiki/Software/systemd/#bugreports⟩. This
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you have corrections or improvements to the information in this
COLOPHON (which is not part of the original manual page), send a mail
to man-pages@man7.org
systemd 234 SD_EVENT_SOURCE_SET_DESCRIPTION(3)
Pages that refer to this page: sd-event(3), sd_event_add_child(3), sd_event_add_defer(3), sd_event_add_io(3), sd_event_add_signal(3), sd_event_add_time(3), sd_event_source_set_userdata(3), systemd.directives(7), systemd.index(7)