context.h File Reference

Connection contexts for asynchrononous communication with a server. More...

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Typedefs
typedef struct pa_context	pa_context
	An opaque connection context to a daemon.
typedef void(*	pa_context_notify_cb_t )(pa_context *c, void *userdata)
	Generic notification callback prototype.
typedef void(*	pa_context_success_cb_t )(pa_context *c, int success, void *userdata)
	A generic callback for operation completion.
Functions
pa_context *	pa_context_new (pa_mainloop_api *mainloop, const char *name)
	Instantiate a new connection context with an abstract mainloop API and an application name.
void	pa_context_unref (pa_context *c)
	Decrease the reference counter of the context by one.
pa_context *	pa_context_ref (pa_context *c)
	Increase the reference counter of the context by one.
void	pa_context_set_state_callback (pa_context *c, pa_context_notify_cb_t cb, void *userdata)
	Set a callback function that is called whenever the context status changes.
int	pa_context_errno (pa_context *c)
	Return the error number of the last failed operation.
int	pa_context_is_pending (pa_context *c)
	Return non-zero if some data is pending to be written to the connection.
pa_context_state_t	pa_context_get_state (pa_context *c)
	Return the current context status.
int	pa_context_connect (pa_context *c, const char *server, pa_context_flags_t flags, const pa_spawn_api *api)
	Connect the context to the specified server.
void	pa_context_disconnect (pa_context *c)
	Terminate the context connection immediately.
pa_operation *	pa_context_drain (pa_context *c, pa_context_notify_cb_t cb, void *userdata)
	Drain the context.
pa_operation *	pa_context_exit_daemon (pa_context *c, pa_context_success_cb_t cb, void *userdata)
	Tell the daemon to exit.
pa_operation *	pa_context_set_default_sink (pa_context *c, const char *name, pa_context_success_cb_t cb, void *userdata)
	Set the name of the default sink.
pa_operation *	pa_context_set_default_source (pa_context *c, const char *name, pa_context_success_cb_t cb, void *userdata)
	Set the name of the default source.
int	pa_context_is_local (pa_context *c)
	Returns 1 when the connection is to a local daemon.
pa_operation *	pa_context_set_name (pa_context *c, const char *name, pa_context_success_cb_t cb, void *userdata)
	Set a different application name for context on the server.
const char *	pa_context_get_server (pa_context *c)
	Return the server name this context is connected to.
uint32_t	pa_context_get_protocol_version (pa_context *c)
	Return the protocol version of the library.
uint32_t	pa_context_get_server_protocol_version (pa_context *c)
	Return the protocol version of the connected server.

---

Detailed Description

Connection contexts for asynchrononous communication with a server.

A pa_context object wraps a connection to a PulseAudio server using its native protocol.

---

Typedef Documentation

typedef struct pa_context pa_context

An opaque connection context to a daemon.

Examples:

pacat.c, and paplay.c.

typedef void(* pa_context_notify_cb_t)(pa_context *c, void *userdata)

Generic notification callback prototype.

typedef void(* pa_context_success_cb_t)(pa_context *c, int success, void *userdata)

A generic callback for operation completion.

---

Function Documentation

int pa_context_connect	(	pa_context *	c,
		const char *	server,
		pa_context_flags_t	flags,
		const pa_spawn_api *	api
	)

Connect the context to the specified server.

If server is NULL, connect to the default server. This routine may but will not always return synchronously on error. Use pa_context_set_state_callback() to be notified when the connection is established. If flags doesn't have PA_NOAUTOSPAWN set and no specific server is specified or accessible a new daemon is spawned. If api is non-NULL, the functions specified in the structure are used when forking a new child process.

Examples:

pacat.c, and paplay.c.

void pa_context_disconnect

(

pa_context *

c

)

Terminate the context connection immediately.

Examples:

pacat.c, and paplay.c.

pa_operation* pa_context_drain	(	pa_context *	c,
		pa_context_notify_cb_t	cb,
		void *	userdata
	)

Drain the context.

If there is nothing to drain, the function returns NULL

Examples:

pacat.c, and paplay.c.

int pa_context_errno

(

pa_context *

c

)

Return the error number of the last failed operation.

Examples:

pacat.c, and paplay.c.

pa_operation* pa_context_exit_daemon	(	pa_context *	c,
		pa_context_success_cb_t	cb,
		void *	userdata
	)

Tell the daemon to exit.

The returned operation is unlikely to complete succesfully, since the daemon probably died before returning a success notification

uint32_t pa_context_get_protocol_version

(

pa_context *

c

)

Return the protocol version of the library.

Since:

0.8

const char* pa_context_get_server

(

pa_context *

c

)

Return the server name this context is connected to.

Since:

0.7

uint32_t pa_context_get_server_protocol_version

(

pa_context *

c

)

Return the protocol version of the connected server.

Since:

0.8

pa_context_state_t pa_context_get_state

(

pa_context *

c

)

Return the current context status.

Examples:

pacat.c, and paplay.c.

int pa_context_is_local

(

pa_context *

c

)

Returns 1 when the connection is to a local daemon.

Returns negative when no connection has been made yet.

Since:

0.5

int pa_context_is_pending

(

pa_context *

c

)

Return non-zero if some data is pending to be written to the connection.

pa_context* pa_context_new	(	pa_mainloop_api *	mainloop,
		const char *	name
	)

Instantiate a new connection context with an abstract mainloop API and an application name.

Examples:

pacat.c, and paplay.c.

pa_context* pa_context_ref

(

pa_context *

c

)

Increase the reference counter of the context by one.

pa_operation* pa_context_set_default_sink	(	pa_context *	c,
		const char *	name,
		pa_context_success_cb_t	cb,
		void *	userdata
	)

Set the name of the default sink.

Since:

0.4

pa_operation* pa_context_set_default_source	(	pa_context *	c,
		const char *	name,
		pa_context_success_cb_t	cb,
		void *	userdata
	)

Set the name of the default source.

Since:

0.4

pa_operation* pa_context_set_name	(	pa_context *	c,
		const char *	name,
		pa_context_success_cb_t	cb,
		void *	userdata
	)

Set a different application name for context on the server.

Since:

0.5

void pa_context_set_state_callback	(	pa_context *	c,
		pa_context_notify_cb_t	cb,
		void *	userdata
	)

Set a callback function that is called whenever the context status changes.

Examples:

pacat.c, and paplay.c.

void pa_context_unref

(

pa_context *

c

)

Decrease the reference counter of the context by one.

Examples:

pacat.c, and paplay.c.