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#ifndef foosubscribehfoo
#define foosubscribehfoo
/***
This file is part of PulseAudio.
Copyright 2004-2006 Lennart Poettering
Copyright 2006 Pierre Ossman <ossman@cendio.se> for Cendio AB
PulseAudio is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published
by the Free Software Foundation; either version 2.1 of the License,
or (at your option) any later version.
PulseAudio is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with PulseAudio; if not, see <http://www.gnu.org/licenses/>.
***/
#include <inttypes.h>
#include <pulse/def.h>
#include <pulse/context.h>
#include <pulse/cdecl.h>
#include <pulse/version.h>
/** \page subscribe Event Subscription
*
* \section overv_sec Overview
*
* The application can be notified, asynchronously, whenever the internal
* layout of the server changes. Possible notifications are described in the
* \ref pa_subscription_event_type and \ref pa_subscription_mask
* enumerations.
*
* The application sets the notification mask using pa_context_subscribe()
* and the function that will be called whenever a notification occurs using
* pa_context_set_subscribe_callback().
*
* The callback will be called with a \ref pa_subscription_event_type_t
* representing the event that caused the callback. Clients can examine what
* object changed using \ref PA_SUBSCRIPTION_EVENT_FACILITY_MASK. The actual
* event type can then be extracted with \ref PA_SUBSCRIPTION_EVENT_TYPE_MASK.
* Please note that the masked values are integers, not flags (so you will
* check the object/event type using a comparison not a binary AND). For
* example, the callback might look something like:
*
@verbatim
void my_subscription_callback(pa_context *c, pa_subscription_event_type_t t,
uint32_t idx, void *userdata) {
if ((t & PA_SUBSCRIPTION_EVENT_FACILITY_MASK) == PA_SUBSCRIPTION_EVENT_SOURCE) {
if ((t & PA_SUBSCRIPTION_EVENT_TYPE_MASK) == PA_SUBSCRIPTION_EVENT_NEW) {
... a source was added, let's do stuff! ...
}
}
}
@endverbatim
*/
/** \file
* Daemon introspection event subscription subsystem.
*
* See also \subpage subscribe
*/
PA_C_DECL_BEGIN
/** Subscription event callback prototype */
typedef void (*pa_context_subscribe_cb_t)(pa_context *c, pa_subscription_event_type_t t, uint32_t idx, void *userdata);
/** Enable event notification */
pa_operation* pa_context_subscribe(pa_context *c, pa_subscription_mask_t m, pa_context_success_cb_t cb, void *userdata);
/** Set the context specific call back function that is called whenever the state of the daemon changes */
void pa_context_set_subscribe_callback(pa_context *c, pa_context_subscribe_cb_t cb, void *userdata);
PA_C_DECL_END
#endif
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