sd_event_source_get_pending(3) — Linux manual page


SD_EVEN..._PENDING(3)  sd_event_source_get_pending SD_EVEN..._PENDING(3)

NAME         top

       sd_event_source_get_pending - Determine pending state of event

SYNOPSIS         top

       #include <systemd/sd-event.h>

       int sd_event_source_get_pending(sd_event_source *source);

DESCRIPTION         top

       sd_event_source_get_pending() may be used to determine whether
       the event source object specified as source has seen events but
       has not been dispatched yet (and thus is marked "pending").

       Event source objects initially are not marked pending, when they
       are created with calls such as sd_event_add_io(3),
       sd_event_add_time(3), with the exception of those created with
       sd_event_add_defer(3) which are immediately marked pending, and
       sd_event_add_exit(3) for which the "pending" concept is not
       defined. For details see the respective manual pages.

       In each event loop iteration one event source of those marked
       pending is dispatched, in the order defined by the event source
       priority, as set with sd_event_source_set_priority(3).

       For I/O event sources, as created with sd_event_add_io(3), the
       call sd_event_source_get_io_revents(3) may be used to query the
       type of event pending in more detail.

RETURN VALUE         top

       On success, sd_event_source_get_pending() returns an integer
       greater than zero when the event source is marked pending, and
       zero when the event source is not marked pending. On failure, it
       returns 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.

           source refers to an event source object created with

           Not enough memory.

           The event loop is already terminated.

           The event loop has been created in a different process,
           library or module instance.

NOTES         top

       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

HISTORY         top

       sd_event_source_get_pending() was added in version 229.

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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       This page was obtained from the project's upstream Git repository
       ⟨⟩ on 2023-12-22.  (At that
       time, the date of the most recent commit that was found in the
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       (which is not part of the original manual page), send a mail to

systemd 255                                        SD_EVEN..._PENDING(3)

Pages that refer to this page: sd-event(3)sd_event_add_io(3)systemd.directives(7)systemd.index(7)