Creating and managing client threads

Typedefs
typedef int(*	jack_thread_creator_t) (jack_native_thread_t *, const pthread_attr_t *, void *(*function) (void *), void *arg) JACK_OPTIONAL_WEAK_EXPORT

Functions
int	jack_client_real_time_priority (jack_client_t *) JACK_OPTIONAL_WEAK_EXPORT
int	jack_client_max_real_time_priority (jack_client_t *) JACK_OPTIONAL_WEAK_EXPORT
int	jack_acquire_real_time_scheduling (jack_native_thread_t thread, int priority) JACK_OPTIONAL_WEAK_EXPORT
int	jack_client_create_thread (jack_client_t *client, jack_native_thread_t *thread, int priority, int realtime, void *(*start_routine)(void *), void *arg) JACK_OPTIONAL_WEAK_EXPORT
int	jack_drop_real_time_scheduling (jack_native_thread_t thread) JACK_OPTIONAL_WEAK_EXPORT
void	jack_set_thread_creator (jack_thread_creator_t creator) JACK_OPTIONAL_WEAK_EXPORT

Detailed Description

Typedef Documentation

jack_thread_creator_t

typedef int(* jack_thread_creator_t) (jack_native_thread_t *, const pthread_attr_t *, void *(*function)(void *), void *arg) JACK_OPTIONAL_WEAK_EXPORT

Function Documentation

jack_acquire_real_time_scheduling()

int jack_acquire_real_time_scheduling	(	jack_native_thread_t	thread,
		int	priority
	)

Attempt to enable realtime scheduling for a thread. On some systems that may require special privileges.

Parameters

thread	POSIX thread ID.
priority	requested thread priority.

Returns

0, if successful; EPERM, if the calling process lacks required realtime privileges; otherwise some other error number.

jack_client_create_thread()

int jack_client_create_thread	(	jack_client_t *	client,
		jack_native_thread_t *	thread,
		int	priority,
		int	realtime,
		void *(*)(void *)	start_routine,
		void *	arg
	)

Create a thread for JACK or one of its clients. The thread is created executing start_routine with arg as its sole argument.

Parameters

client	the JACK client for whom the thread is being created. May be NULL if the client is being created within the JACK server.
thread	place to return POSIX thread ID.
priority	thread priority, if realtime.
realtime	true for the thread to use realtime scheduling. On some systems that may require special privileges.
start_routine	function the thread calls when it starts.
arg	parameter passed to the start_routine.

Returns

0, if successful; otherwise some error number.

jack_client_max_real_time_priority()

int jack_client_max_real_time_priority

(

jack_client_t *

)

Returns

if JACK is running with realtime scheduling, this returns the maximum priority that a JACK client thread should use if the thread is subject to realtime scheduling. Otherwise returns -1.

jack_client_real_time_priority()

int jack_client_real_time_priority

(

jack_client_t *

)

Returns

if JACK is running with realtime scheduling, this returns the priority that any JACK-created client threads will run at. Otherwise returns -1.

jack_drop_real_time_scheduling()

int jack_drop_real_time_scheduling

(

jack_native_thread_t

thread

)

Drop realtime scheduling for a thread.

Parameters

thread

POSIX thread ID.

Returns

0, if successful; otherwise an error number.

jack_set_thread_creator()

void jack_set_thread_creator

(

jack_thread_creator_t

creator

)

This function can be used in very very specialized cases where it is necessary that client threads created by JACK are created by something other than pthread_create(). After it is used, any threads that JACK needs for the client will will be created by calling the function passed to this function.

No normal application/client should consider calling this. The specific case for which it was created involves running win32/x86 plugins under Wine on Linux, where it is necessary that all threads that might call win32 functions are known to Wine.

Parameters

creator

a function that creates a new thread