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_child(3),
       sd_event_add_signal(3), sd_event_add_defer(3), sd_event_source_unref(3)