x SuSE Linux 13.1-RELEASE x
x SuSE Linux 13.1-RELEASEx
SD_EVENT_EXIT(3) sd_event_exit SD_EVENT_EXIT(3)
NAME
sd_event_exit, sd_event_get_exit_code - Ask the event loop to exit
SYNOPSIS
#include <systemd/sd-event.h>
int sd_event_exit(sd_event *event, int code);
int sd_event_get_exit_code(sd_event *event, int *code);
DESCRIPTION
sd_event_exit() requests the event loop specified in the event event
loop object to exit. The code parameter may be any integer value and is
returned as-is by sd_event_loop(3) after the last event loop iteration.
It may also be queried using sd_event_get_exit_code(), see below.
When exiting is requested the event loop will stop listening for and
dispatching regular event sources. Instead it will proceed with
executing only event sources registered with sd_event_add_exit(3) in
the order defined by their priority. After all exit event sources have
been dispatched the event loop is terminated.
If sd_event_exit() is invoked a second time while the event loop is
still processing exit event sources, the exit code stored in the event
loop object is updated, but otherwise no further operation is executed.
sd_event_get_exit_code() may be used to query the exit code passed into
sd_event_exit() earlier.
While the full positive and negative integer ranges may be used for the
exit code, care should be taken not pick exit codes that conflict with
regular exit codes returned by sd_event_loop(), if these exit codes
shall be distinguishable.
Note that for most event source types passing the callback pointer as
NULL in the respective constructor call (i.e. in sd_event_add_time(3),
sd_event_add_signal(3), ...) has the effect of sd_event_exit() being
invoked once the event source triggers, with the specified userdata
pointer cast to an integer as the exit code parameter. This is useful
to automatically terminate an event loop after some condition, such as
a time-out or reception of SIGTERM or similar. See the documentation
for the respective constructor call for details.
RETURN VALUE
On success, sd_event_exit() and sd_event_get_exit_code() return 0 or a
positive integer. On failure, they return a negative errno-style error
code.
Errors
Returned errors may indicate the following problems:
-EINVAL
The event loop object or error code pointer are invalid.
-ECHILD
The event loop was created in a different process, library or
module instance.
-ESTALE
The event loop has exited already and all exit handlers are already
processed.
-ENODATA
The event loop has not been requested to exit yet.
NOTES
Functions described here are available as a shared library, which can
be compiled against and linked to with the libsystemd pkg-config(1)
file.
The code described here uses getenv(3), which is declared to be not
multi-thread-safe. This means that the code calling the functions
described here must not call setenv(3) from a parallel thread. It is
recommended to only do calls to setenv() from an early phase of the
program when no other threads have been started.
SEE ALSO
systemd(1), sd-event(3), sd_event_new(3), sd_event_add_exit(3),
sd_event_add_time(3), sd_event_add_signal(3), sd_event_add_io(3),
sd_event_add_defer(3), sd_event_add_inotify(3)
systemd 254 SD_EVENT_EXIT(3)
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