NAME

       sd_event_source_get_pending - Determine pending state of event sources

SYNOPSIS

       #include <systemd/sd-event.h>

       int sd_event_source_get_pending(sd_event_source *source);

DESCRIPTION

       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

       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.

   Errors
       Returned errors may indicate the following problems:

       -EINVAL
           source is not a valid pointer to an sd_event_source object.

       -EDOM
           source refers to an event source object created with sd_event_add_exit(3).

       -ENOMEM
           Not enough memory.

       -ESTALE
           The event loop is already terminated.

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

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_unref(3)