Путеводитель по Руководству Linux

  User  |  Syst  |  Libr  |  Device  |  Files  |  Other  |  Admin  |  Head  |



   sd_event_source_set_userdata    ( 3 )

установить или получить указатель пользовательских данных источников событий (Set or retrieve user data pointer of event sources)

Имя (Name)

sd_event_source_set_userdata, sd_event_source_get_userdata - Set
       or retrieve user data pointer of event sources

Синопсис (Synopsis)

#include <systemd/sd-event.h>

void* sd_event_source_set_userdata(sd_event_source *source, void *userdata);

void* sd_event_source_get_userdata(sd_event_source *source);


Описание (Description)

sd_event_source_set_userdata() may be used to set an arbitrary
       user data pointer for the event source object specified as
       source. The user data pointer is usually specified when creating
       an event source object with calls such as sd_event_add_io(3) or
       sd_event_add_time(3), and may be updated with this call. The user
       data pointer is also passed to all handler callback functions
       associated with the event source. The userdata parameter
       specifies the new user data pointer to set, the function returns
       the previous user data pointer. Note that NULL is a valid user
       data pointer.

sd_event_source_get_userdata() may be used to query the current user data pointer assigned to the event source object source.


Возвращаемое значение (Return value)

On success, sd_event_source_set_userdata() and
       sd_event_source_get_userdata() return the previously set user
       data pointer. On failure, they return NULL.

Примечание (Note)

These APIs are implemented as a shared library, which can be
       compiled and linked to with the libsystemd pkg-config(1) file.

Смотри также (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_set_description(3)