Adding upstream version 0.3.65.upstream/0.3.65upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1477 insertions, 0 deletions

diff --git a/pipewire-jack/jack/jack.h b/pipewire-jack/jack/jack.h
new file mode 100644
index 0000000..2b83cb1
--- /dev/null
+++ b/pipewire-jack/jack/jack.h
@@ -0,0 +1,1477 @@
+/*
+  Copyright (C) 2001 Paul Davis
+  Copyright (C) 2004 Jack O'Quin
+
+  This program 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.
+
+  This program 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 Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+*/
+
+#ifndef __jack_h__
+#define __jack_h__
+
+#ifdef __cplusplus
+extern "C"
+{
+#endif
+
+#include <jack/systemdeps.h>
+#include <jack/types.h>
+#include <jack/transport.h>
+
+/**
+ * Note: More documentation can be found in jack/types.h.
+ */
+
+    /*************************************************************
+     * NOTE: JACK_WEAK_EXPORT ***MUST*** be used on every function
+     * added to the JACK API after the 0.116.2 release.
+     *
+     * Functions that predate this release are marked with
+     * JACK_WEAK_OPTIONAL_EXPORT which can be defined at compile
+     * time in a variety of ways. The default definition is empty,
+     * so that these symbols get normal linkage. If you wish to
+     * use all JACK symbols with weak linkage, include
+     * <jack/weakjack.h> before jack.h.
+     *************************************************************/
+
+#include <jack/weakmacros.h>
+
+/**
+ * Call this function to get version of the JACK, in form of several numbers
+ *
+ * @param major_ptr pointer to variable receiving major version of JACK.
+ *
+ * @param minor_ptr pointer to variable receiving minor version of JACK.
+ *
+ * @param major_ptr pointer to variable receiving micro version of JACK.
+ *
+ * @param major_ptr pointer to variable receiving protocol version of JACK.
+ *
+ */
+void
+jack_get_version(
+    int *major_ptr,
+    int *minor_ptr,
+    int *micro_ptr,
+    int *proto_ptr) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * Call this function to get version of the JACK, in form of a string
+ *
+ * @return Human readable string describing JACK version being used.
+ *
+ */
+const char *
+jack_get_version_string(void) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * @defgroup ClientFunctions Creating & manipulating clients
+ * @{
+ */
+
+/**
+ * Open an external client session with a JACK server.  This interface
+ * is more complex but more powerful than jack_client_new().  With it,
+ * clients may choose which of several servers to connect, and control
+ * whether and how to start the server automatically, if it was not
+ * already running.  There is also an option for JACK to generate a
+ * unique client name, when necessary.
+ *
+ * @param client_name of at most jack_client_name_size() characters.
+ * The name scope is local to each server.  Unless forbidden by the
+ * @ref JackUseExactName option, the server will modify this name to
+ * create a unique variant, if needed.
+ *
+ * @param options formed by OR-ing together @ref JackOptions bits.
+ * Only the @ref JackOpenOptions bits are allowed.
+ *
+ * @param status (if non-NULL) an address for JACK to return
+ * information from the open operation.  This status word is formed by
+ * OR-ing together the relevant @ref JackStatus bits.
+ *
+ *
+ * <b>Optional parameters:</b> depending on corresponding [@a options
+ * bits] additional parameters may follow @a status (in this order).
+ *
+ * @arg [@ref JackServerName] <em>(char *) server_name</em> selects
+ * from among several possible concurrent server instances.  Server
+ * names are unique to each user.  If unspecified, use "default"
+ * unless \$JACK_DEFAULT_SERVER is defined in the process environment.
+ *
+ * @return Opaque client handle if successful.  If this is NULL, the
+ * open operation failed, @a *status includes @ref JackFailure and the
+ * caller is not a JACK client.
+ */
+jack_client_t * jack_client_open (const char *client_name,
+                                  jack_options_t options,
+                                  jack_status_t *status, ...) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+* \bold THIS FUNCTION IS DEPRECATED AND SHOULD NOT BE USED IN
+*  NEW JACK CLIENTS
+*
+* @deprecated Please use jack_client_open().
+*/
+jack_client_t * jack_client_new (const char *client_name) JACK_OPTIONAL_WEAK_DEPRECATED_EXPORT;
+
+/**
+ * Disconnects an external client from a JACK server.
+ *
+ * @return 0 on success, otherwise a non-zero error code
+ */
+int jack_client_close (jack_client_t *client) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * @return the maximum number of characters in a JACK client name
+ * including the final NULL character.  This value is a constant.
+ */
+int jack_client_name_size (void) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * @return pointer to actual client name.  This is useful when @ref
+ * JackUseExactName is not specified on open and @ref
+ * JackNameNotUnique status was returned.  In that case, the actual
+ * name will differ from the @a client_name requested.
+ */
+char * jack_get_client_name (jack_client_t *client) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * Get the session ID for a client name.
+ *
+ * The session manager needs this to reassociate a client name to the session_id.
+ *
+ * The caller is responsible for calling jack_free(3) on any non-NULL
+ * returned value.
+ */
+char *jack_get_uuid_for_client_name (jack_client_t *client,
+                                     const char    *client_name) JACK_WEAK_EXPORT;
+
+/**
+ * Get the client name for a session_id.
+ *
+ * In order to snapshot the graph connections, the session manager needs to map
+ * session_ids to client names.
+ *
+ * The caller is responsible for calling jack_free(3) on any non-NULL
+ * returned value.
+ */
+char *jack_get_client_name_by_uuid (jack_client_t *client,
+                                    const char    *client_uuid ) JACK_WEAK_EXPORT;
+
+/**
+ * Load an internal client into the Jack server.
+ *
+ * Internal clients run inside the JACK server process.  They can use
+ * most of the same functions as external clients.  Each internal
+ * client must declare jack_initialize() and jack_finish() entry
+ * points, called at load and unload times.  See inprocess.c for an
+ * example of how to write an internal client.
+ *
+ * @deprecated Please use jack_internal_client_load().
+ *
+ * @param client_name of at most jack_client_name_size() characters.
+ *
+ * @param load_name of a shared object file containing the code for
+ * the new client.
+ *
+ * @param load_init an arbitrary string passed to the jack_initialize()
+ * routine of the new client (may be NULL).
+ *
+ * @return 0 if successful.
+ */
+int jack_internal_client_new (const char *client_name,
+                              const char *load_name,
+                              const char *load_init) JACK_OPTIONAL_WEAK_DEPRECATED_EXPORT;
+
+/**
+ * Remove an internal client from a JACK server.
+ *
+ * @deprecated Please use jack_internal_client_unload().
+ */
+void jack_internal_client_close (const char *client_name) JACK_OPTIONAL_WEAK_DEPRECATED_EXPORT;
+
+/**
+ * Tell the Jack server that the program is ready to start processing
+ * audio.
+ *
+ * @return 0 on success, otherwise a non-zero error code
+ */
+int jack_activate (jack_client_t *client) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * Tell the Jack server to remove this @a client from the process
+ * graph.  Also, disconnect all ports belonging to it, since inactive
+ * clients have no port connections.
+ *
+ * @return 0 on success, otherwise a non-zero error code
+ */
+int jack_deactivate (jack_client_t *client) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * @return pid of client. If not available, 0 will be returned.
+ */
+int jack_get_client_pid (const char *name) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * @return the pthread ID of the thread running the JACK client side
+ * real-time code.
+ */
+jack_native_thread_t jack_client_thread_id (jack_client_t *client) JACK_OPTIONAL_WEAK_EXPORT;
+
+/*@}*/
+
+/**
+ * @param client pointer to JACK client structure.
+ *
+ * Check if the JACK subsystem is running with -R (--realtime).
+ *
+ * @return 1 if JACK is running realtime, 0 otherwise
+ */
+int jack_is_realtime (jack_client_t *client) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * @defgroup NonCallbackAPI The non-callback API
+ * @{
+ */
+
+/**
+ * \bold THIS FUNCTION IS DEPRECATED AND SHOULD NOT BE USED IN
+ *  NEW JACK CLIENTS.
+ *
+ * @deprecated Please use jack_cycle_wait() and jack_cycle_signal() functions.
+ */
+jack_nframes_t jack_thread_wait (jack_client_t *client, int status) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * Wait until this JACK client should process data.
+ *
+ * @param client - pointer to a JACK client structure
+ *
+ * @return the number of frames of data to process
+ */
+jack_nframes_t jack_cycle_wait (jack_client_t* client) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * Signal next clients in the graph.
+ *
+ * @param client - pointer to a JACK client structure
+ * @param status - if non-zero, calling thread should exit
+ */
+void jack_cycle_signal (jack_client_t* client, int status) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * Tell the Jack server to call @a thread_callback in the RT thread.
+ * Typical use are in conjunction with @a jack_cycle_wait and @a jack_cycle_signal functions.
+ * The code in the supplied function must be suitable for real-time
+ * execution.  That means that it cannot call functions that might
+ * block for a long time. This includes malloc, free, printf,
+ * pthread_mutex_lock, sleep, wait, poll, select, pthread_join,
+ * pthread_cond_wait, etc, etc. See
+ * http://jackit.sourceforge.net/docs/design/design.html#SECTION00411000000000000000
+ * for more information.
+ *
+ * NOTE: this function cannot be called while the client is activated
+ * (after jack_activate has been called.)
+ *
+ * @return 0 on success, otherwise a non-zero error code.
+*/
+int jack_set_process_thread(jack_client_t* client, JackThreadCallback thread_callback, void *arg) JACK_OPTIONAL_WEAK_EXPORT;
+
+/*@}*/
+
+/**
+ * @defgroup ClientCallbacks Setting Client Callbacks
+ * @{
+ */
+
+/**
+ * Tell JACK to call @a thread_init_callback once just after
+ * the creation of the thread in which all other callbacks
+ * will be handled.
+ *
+ * The code in the supplied function does not need to be
+ * suitable for real-time execution.
+ *
+ * NOTE: this function cannot be called while the client is activated
+ * (after jack_activate has been called.)
+ *
+ * @return 0 on success, otherwise a non-zero error code, causing JACK
+ * to remove that client from the process() graph.
+ */
+int jack_set_thread_init_callback (jack_client_t *client,
+                                   JackThreadInitCallback thread_init_callback,
+                                   void *arg) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * @param client pointer to JACK client structure.
+ * @param function The jack_shutdown function pointer.
+ * @param arg The arguments for the jack_shutdown function.
+ *
+ * Register a function (and argument) to be called if and when the
+ * JACK server shuts down the client thread.  The function must
+ * be written as if it were an asynchronous POSIX signal
+ * handler --- use only async-safe functions, and remember that it
+ * is executed from another thread.  A typical function might
+ * set a flag or write to a pipe so that the rest of the
+ * application knows that the JACK client thread has shut
+ * down.
+ *
+ * NOTE: clients do not need to call this.  It exists only
+ * to help more complex clients understand what is going
+ * on.  It should be called before jack_client_activate().
+ *
+ * NOTE: if a client calls this AND jack_on_info_shutdown(), then
+ * in case of a client thread shutdown, the callback
+ * passed to this function will not be called, and the one passed to
+ * jack_on_info_shutdown() will.
+ *
+ * NOTE: application should typically signal another thread to correctly 
+ * finish cleanup, that is by calling "jack_client_close" 
+ * (since "jack_client_close" cannot be called directly in the context 
+ * of the thread that calls the shutdown callback).
+ */
+void jack_on_shutdown (jack_client_t *client,
+                       JackShutdownCallback shutdown_callback, void *arg) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * @param client pointer to JACK client structure.
+ * @param function The jack_info_shutdown function pointer.
+ * @param arg The arguments for the jack_info_shutdown function.
+ *
+ * Register a function (and argument) to be called if and when the
+ * JACK server shuts down the client thread.  The function must
+ * be written as if it were an asynchronous POSIX signal
+ * handler --- use only async-safe functions, and remember that it
+ * is executed from another thread.  A typical function might
+ * set a flag or write to a pipe so that the rest of the
+ * application knows that the JACK client thread has shut
+ * down.
+ *
+ * NOTE: clients do not need to call this.  It exists only
+ * to help more complex clients understand what is going
+ * on.  It should be called before jack_client_activate().
+ *
+ * NOTE: if a client calls this AND jack_on_shutdown(), then
+ * in case of a client thread shutdown, the callback passed to
+ * jack_on_info_shutdown() will be called.
+ *
+ * NOTE: application should typically signal another thread to correctly 
+ * finish cleanup, that is by calling "jack_client_close" 
+ * (since "jack_client_close" cannot be called directly in the context 
+ * of the thread that calls the shutdown callback).
+ */
+void jack_on_info_shutdown (jack_client_t *client,
+                            JackInfoShutdownCallback shutdown_callback, void *arg) JACK_WEAK_EXPORT;
+
+/**
+ * Tell the Jack server to call @a process_callback whenever there is
+ * work be done, passing @a arg as the second argument.
+ *
+ * The code in the supplied function must be suitable for real-time
+ * execution.  That means that it cannot call functions that might
+ * block for a long time. This includes malloc, free, printf,
+ * pthread_mutex_lock, sleep, wait, poll, select, pthread_join,
+ * pthread_cond_wait, etc, etc. See
+ * http://jackit.sourceforge.net/docs/design/design.html#SECTION00411000000000000000
+ * for more information.
+ *
+ * NOTE: this function cannot be called while the client is activated
+ * (after jack_activate has been called.)
+ *
+ * @return 0 on success, otherwise a non-zero error code.
+ */
+int jack_set_process_callback (jack_client_t *client,
+                               JackProcessCallback process_callback,
+                               void *arg) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * Tell the Jack server to call @a freewheel_callback
+ * whenever we enter or leave "freewheel" mode, passing @a
+ * arg as the second argument. The first argument to the
+ * callback will be non-zero if JACK is entering freewheel
+ * mode, and zero otherwise.
+ *
+ * All "notification events" are received in a separated non RT thread,
+ * the code in the supplied function does not need to be
+ * suitable for real-time execution.
+ *
+ * NOTE: this function cannot be called while the client is activated
+ * (after jack_activate has been called.)
+ *
+ * @return 0 on success, otherwise a non-zero error code.
+ */
+int jack_set_freewheel_callback (jack_client_t *client,
+                                 JackFreewheelCallback freewheel_callback,
+                                 void *arg) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * Tell JACK to call @a bufsize_callback whenever the size of the
+ * buffer that will be passed to the @a process_callback is about to
+ * change.  Clients that depend on knowing the buffer size must supply
+ * a @a bufsize_callback before activating themselves.
+ *
+ * All "notification events" are received in a separated non RT thread,
+ * the code in the supplied function does not need to be
+ * suitable for real-time execution.
+ *
+ * NOTE: this function cannot be called while the client is activated
+ * (after jack_activate has been called.)
+ *
+ * @param client pointer to JACK client structure.
+ * @param bufsize_callback function to call when the buffer size changes.
+ * @param arg argument for @a bufsize_callback.
+ *
+ * @return 0 on success, otherwise a non-zero error code
+ */
+int jack_set_buffer_size_callback (jack_client_t *client,
+                                   JackBufferSizeCallback bufsize_callback,
+                                   void *arg) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * Tell the Jack server to call @a srate_callback whenever the system
+ * sample rate changes.
+ *
+ * All "notification events" are received in a separated non RT thread,
+ * the code in the supplied function does not need to be
+ * suitable for real-time execution.
+ *
+ * NOTE: this function cannot be called while the client is activated
+ * (after jack_activate has been called.)
+ *
+ * @return 0 on success, otherwise a non-zero error code
+ */
+int jack_set_sample_rate_callback (jack_client_t *client,
+                                   JackSampleRateCallback srate_callback,
+                                   void *arg) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * Tell the JACK server to call @a client_registration_callback whenever a
+ * client is registered or unregistered, passing @a arg as a parameter.
+ *
+ * All "notification events" are received in a separated non RT thread,
+ * the code in the supplied function does not need to be
+ * suitable for real-time execution.
+ *
+ * NOTE: this function cannot be called while the client is activated
+ * (after jack_activate has been called.)
+ *
+ * @return 0 on success, otherwise a non-zero error code
+ */
+int jack_set_client_registration_callback (jack_client_t *client,
+                                            JackClientRegistrationCallback
+                                            registration_callback, void *arg) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * Tell the JACK server to call @a registration_callback whenever a
+ * port is registered or unregistered, passing @a arg as a parameter.
+ *
+ * All "notification events" are received in a separated non RT thread,
+ * the code in the supplied function does not need to be
+ * suitable for real-time execution.
+ *
+ * NOTE: this function cannot be called while the client is activated
+ * (after jack_activate has been called.)
+ *
+ * @return 0 on success, otherwise a non-zero error code
+ */
+ int jack_set_port_registration_callback (jack_client_t *client,
+                                          JackPortRegistrationCallback
+                                          registration_callback, void *arg) JACK_OPTIONAL_WEAK_EXPORT;
+
+ /**
+ * Tell the JACK server to call @a connect_callback whenever a
+ * port is connected or disconnected, passing @a arg as a parameter.
+ *
+ * All "notification events" are received in a separated non RT thread,
+ * the code in the supplied function does not need to be
+ * suitable for real-time execution.
+ *
+ * NOTE: this function cannot be called while the client is activated
+ * (after jack_activate has been called.)
+ *
+ * @return 0 on success, otherwise a non-zero error code
+ */
+int jack_set_port_connect_callback (jack_client_t *client,
+                                    JackPortConnectCallback
+                                    connect_callback, void *arg) JACK_OPTIONAL_WEAK_EXPORT;
+
+ /**
+ * Tell the JACK server to call @a rename_callback whenever a
+ * port is renamed, passing @a arg as a parameter.
+ *
+ * All "notification events" are received in a separated non RT thread,
+ * the code in the supplied function does not need to be
+ * suitable for real-time execution.
+ *
+ * NOTE: this function cannot be called while the client is activated
+ * (after jack_activate has been called.)
+ *
+ * @return 0 on success, otherwise a non-zero error code
+ */
+int jack_set_port_rename_callback (jack_client_t *client,
+                                   JackPortRenameCallback
+                                   rename_callback, void *arg) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * Tell the JACK server to call @a graph_callback whenever the
+ * processing graph is reordered, passing @a arg as a parameter.
+ *
+ * All "notification events" are received in a separated non RT thread,
+ * the code in the supplied function does not need to be
+ * suitable for real-time execution.
+ *
+ * NOTE: this function cannot be called while the client is activated
+ * (after jack_activate has been called.)
+ *
+ * @return 0 on success, otherwise a non-zero error code
+ */
+int jack_set_graph_order_callback (jack_client_t *client,
+                                   JackGraphOrderCallback graph_callback,
+                                   void *) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * Tell the JACK server to call @a xrun_callback whenever there is a
+ * xrun, passing @a arg as a parameter.
+ *
+ * All "notification events" are received in a separated non RT thread,
+ * the code in the supplied function does not need to be
+ * suitable for real-time execution.
+ *
+ * NOTE: this function cannot be called while the client is activated
+ * (after jack_activate has been called.)
+ *
+ * @return 0 on success, otherwise a non-zero error code
+ */
+int jack_set_xrun_callback (jack_client_t *client,
+                            JackXRunCallback xrun_callback, void *arg) JACK_OPTIONAL_WEAK_EXPORT;
+
+/*@}*/
+
+/**
+ * Tell the Jack server to call @a latency_callback whenever it
+ * is necessary to recompute the latencies for some or all
+ * Jack ports.
+ *
+ * @a latency_callback will be called twice each time it is
+ * needed, once being passed JackCaptureLatency and once
+ * JackPlaybackLatency. See @ref LatencyFunctions for
+ * the definition of each type of latency and related functions.
+ *
+ * <b>IMPORTANT: Most JACK clients do NOT need to register a latency
+ * callback.</b>
+ *
+ * Clients that meet any of the following conditions do NOT
+ * need to register a latency callback:
+ *
+ *    - have only input ports
+ *    - have only output ports
+ *    - their output is totally unrelated to their input
+ *    - their output is not delayed relative to their input
+ *        (i.e. data that arrives in a given process()
+ *         callback is processed and output again in the
+ *         same callback)
+ *
+ * Clients NOT registering a latency callback MUST also
+ * satisfy this condition:
+ *
+ *    - have no multiple distinct internal signal pathways
+ *
+ * This means that if your client has more than 1 input and
+ * output port, and considers them always "correlated"
+ * (e.g. as a stereo pair), then there is only 1 (e.g. stereo)
+ * signal pathway through the client. This would be true,
+ * for example, of a stereo FX rack client that has a
+ * left/right input pair and a left/right output pair.
+ *
+ * However, this is somewhat a matter of perspective. The
+ * same FX rack client could be connected so that its
+ * two input ports were connected to entirely separate
+ * sources. Under these conditions, the fact that the client
+ * does not register a latency callback MAY result
+ * in port latency values being incorrect.
+ *
+ * Clients that do not meet any of those conditions SHOULD
+ * register a latency callback.
+ *
+ * Another case is when a client wants to use
+ * @ref jack_port_get_latency_range(), which only returns meaningful
+ * values when ports get connected and latency values change.
+ *
+ * See the documentation for  @ref jack_port_set_latency_range()
+ * on how the callback should operate. Remember that the @a mode
+ * argument given to the latency callback will need to be
+ * passed into @ref jack_port_set_latency_range()
+ *
+ * @return 0 on success, otherwise a non-zero error code
+ */
+int jack_set_latency_callback (jack_client_t *client,
+			       JackLatencyCallback latency_callback,
+			       void *) JACK_WEAK_EXPORT;
+/*@}*/
+
+/**
+ * @defgroup ServerClientControl Controlling & querying JACK server operation
+ * @{
+ */
+
+/**
+ * Start/Stop JACK's "freewheel" mode.
+ *
+ * When in "freewheel" mode, JACK no longer waits for
+ * any external event to begin the start of the next process
+ * cycle.
+ *
+ * As a result, freewheel mode causes "faster than realtime"
+ * execution of a JACK graph. If possessed, real-time
+ * scheduling is dropped when entering freewheel mode, and
+ * if appropriate it is reacquired when stopping.
+ *
+ * IMPORTANT: on systems using capabilities to provide real-time
+ * scheduling (i.e. Linux kernel 2.4), if onoff is zero, this function
+ * must be called from the thread that originally called jack_activate().
+ * This restriction does not apply to other systems (e.g. Linux kernel 2.6
+ * or OS X).
+ *
+ * @param client pointer to JACK client structure
+ * @param onoff  if non-zero, freewheel mode starts. Otherwise
+ *                  freewheel mode ends.
+ *
+ * @return 0 on success, otherwise a non-zero error code.
+ */
+int jack_set_freewheel(jack_client_t* client, int onoff) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * Change the buffer size passed to the @a process_callback.
+ *
+ * This operation stops the JACK engine process cycle, then calls all
+ * registered @a bufsize_callback functions before restarting the
+ * process cycle.  This will cause a gap in the audio flow, so it
+ * should only be done at appropriate stopping points.
+ *
+ * @see jack_set_buffer_size_callback()
+ *
+ * @param client pointer to JACK client structure.
+ * @param nframes new buffer size.  Must be a power of two.
+ *
+ * @return 0 on success, otherwise a non-zero error code
+ */
+int jack_set_buffer_size (jack_client_t *client, jack_nframes_t nframes) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * @return the sample rate of the jack system, as set by the user when
+ * jackd was started.
+ */
+jack_nframes_t jack_get_sample_rate (jack_client_t *) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * @return the current maximum size that will ever be passed to the @a
+ * process_callback.  It should only be used *before* the client has
+ * been activated.  This size may change, clients that depend on it
+ * must register a @a bufsize_callback so they will be notified if it
+ * does.
+ *
+ * @see jack_set_buffer_size_callback()
+ */
+jack_nframes_t jack_get_buffer_size (jack_client_t *) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * Old-style interface to become the timebase for the entire JACK
+ * subsystem.
+ *
+ * @deprecated This function still exists for compatibility with the
+ * earlier transport interface, but it does nothing.  Instead, see
+ * transport.h and use jack_set_timebase_callback().
+ *
+ * @return ENOSYS, function not implemented.
+ */
+int jack_engine_takeover_timebase (jack_client_t *) JACK_OPTIONAL_WEAK_DEPRECATED_EXPORT;
+
+/**
+ * @return the current CPU load estimated by JACK.  This is a running
+ * average of the time it takes to execute a full process cycle for
+ * all clients as a percentage of the real time available per cycle
+ * determined by the buffer size and sample rate.
+ */
+float jack_cpu_load (jack_client_t *client) JACK_OPTIONAL_WEAK_EXPORT;
+
+/*@}*/
+
+/**
+ * @defgroup PortFunctions Creating & manipulating ports
+ * @{
+ */
+
+/**
+ * Create a new port for the client. This is an object used for moving
+ * data of any type in or out of the client.  Ports may be connected
+ * in various ways.
+ *
+ * Each port has a short name.  The port's full name contains the name
+ * of the client concatenated with a colon (:) followed by its short
+ * name.  The jack_port_name_size() is the maximum length of this full
+ * name.  Exceeding that will cause the port registration to fail and
+ * return NULL.
+ *
+ * The @a port_name must be unique among all ports owned by this client.
+ * If the name is not unique, the registration will fail.
+ *
+ * All ports have a type, which may be any non-NULL and non-zero
+ * length string, passed as an argument.  Some port types are built
+ * into the JACK API, currently only JACK_DEFAULT_AUDIO_TYPE.
+ *
+ * @param client pointer to JACK client structure.
+ * @param port_name non-empty short name for the new port (not
+ * including the leading @a "client_name:"). Must be unique.
+ * @param port_type port type name.  If longer than
+ * jack_port_type_size(), only that many characters are significant.
+ * @param flags @ref JackPortFlags bit mask.
+ * @param buffer_size must be non-zero if this is not a built-in @a
+ * port_type.  Otherwise, it is ignored.
+ *
+ * @return jack_port_t pointer on success, otherwise NULL.
+ */
+jack_port_t * jack_port_register (jack_client_t *client,
+                                  const char *port_name,
+                                  const char *port_type,
+                                  unsigned long flags,
+                                  unsigned long buffer_size) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * Remove the port from the client, disconnecting any existing
+ * connections.
+ *
+ * @return 0 on success, otherwise a non-zero error code
+ */
+int jack_port_unregister (jack_client_t *client, jack_port_t *port) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * This returns a pointer to the memory area associated with the
+ * specified port. For an output port, it will be a memory area
+ * that can be written to; for an input port, it will be an area
+ * containing the data from the port's connection(s), or
+ * zero-filled. if there are multiple inbound connections, the data
+ * will be mixed appropriately.
+ *
+ * FOR OUTPUT PORTS ONLY : DEPRECATED in Jack 2.0 !!
+ * ---------------------------------------------------
+ * You may cache the value returned, but only between calls to
+ * your "blocksize" callback. For this reason alone, you should
+ * either never cache the return value or ensure you have
+ * a "blocksize" callback and be sure to invalidate the cached
+ * address from there.
+ *
+ * Caching output ports is DEPRECATED in Jack 2.0, due to some new optimization (like "pipelining").
+ * Port buffers have to be retrieved in each callback for proper functioning.
+ */
+void * jack_port_get_buffer (jack_port_t *port, jack_nframes_t) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * @return the UUID of the jack_port_t
+ *
+ * @see jack_uuid_to_string() to convert into a string representation
+ */
+jack_uuid_t jack_port_uuid (const jack_port_t *port) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * @return the full name of the jack_port_t (including the @a
+ * "client_name:" prefix).
+ *
+ * @see jack_port_name_size().
+ */
+const char * jack_port_name (const jack_port_t *port) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * @return the short name of the jack_port_t (not including the @a
+ * "client_name:" prefix).
+ *
+ * @see jack_port_name_size().
+ */
+const char * jack_port_short_name (const jack_port_t *port) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * @return the @ref JackPortFlags of the jack_port_t.
+ */
+int jack_port_flags (const jack_port_t *port) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * @return the @a port type, at most jack_port_type_size() characters
+ * including a final NULL.
+ */
+const char * jack_port_type (const jack_port_t *port) JACK_OPTIONAL_WEAK_EXPORT;
+
+ /**
+ * @return the @a port type id.
+ */
+jack_port_type_id_t jack_port_type_id (const jack_port_t *port) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * @return TRUE if the jack_port_t belongs to the jack_client_t.
+ */
+int jack_port_is_mine (const jack_client_t *client, const jack_port_t *port) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * @return number of connections to or from @a port.
+ *
+ * @pre The calling client must own @a port.
+ */
+int jack_port_connected (const jack_port_t *port) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * @return TRUE if the locally-owned @a port is @b directly connected
+ * to the @a port_name.
+ *
+ * @see jack_port_name_size()
+ */
+int jack_port_connected_to (const jack_port_t *port,
+                            const char *port_name) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * @return a null-terminated array of full port names to which the @a
+ * port is connected.  If none, returns NULL.
+ *
+ * The caller is responsible for calling jack_free() on any non-NULL
+ * returned value.
+ *
+ * @param port locally owned jack_port_t pointer.
+ *
+ * @see jack_port_name_size(), jack_port_get_all_connections()
+ */
+const char ** jack_port_get_connections (const jack_port_t *port) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * @return a null-terminated array of full port names to which the @a
+ * port is connected.  If none, returns NULL.
+ *
+ * The caller is responsible for calling jack_free() on any non-NULL
+ * returned value.
+ *
+ * This differs from jack_port_get_connections() in two important
+ * respects:
+ *
+ *     1) You may not call this function from code that is
+ *          executed in response to a JACK event. For example,
+ *          you cannot use it in a GraphReordered handler.
+ *
+ *     2) You need not be the owner of the port to get information
+ *          about its connections.
+ *
+ * @see jack_port_name_size()
+ */
+const char ** jack_port_get_all_connections (const jack_client_t *client,
+                                             const jack_port_t *port) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ *
+ * @deprecated This function will be removed from a future version
+ * of JACK. Do not use it. There is no replacement. It has
+ * turned out to serve essentially no purpose in real-life
+ * JACK clients.
+ */
+int jack_port_tie (jack_port_t *src, jack_port_t *dst) JACK_OPTIONAL_WEAK_DEPRECATED_EXPORT;
+
+/**
+ *
+ * @deprecated This function will be removed from a future version
+ * of JACK. Do not use it. There is no replacement. It has
+ * turned out to serve essentially no purpose in real-life
+ * JACK clients.
+ */
+int jack_port_untie (jack_port_t *port) JACK_OPTIONAL_WEAK_DEPRECATED_EXPORT;
+
+/**
+ * \bold THIS FUNCTION IS DEPRECATED AND SHOULD NOT BE USED IN
+ *  NEW JACK CLIENTS
+ *
+ * Modify a port's short name.  May be called at any time.  If the
+ * resulting full name (including the @a "client_name:" prefix) is
+ * longer than jack_port_name_size(), it will be truncated.
+ *
+ * @return 0 on success, otherwise a non-zero error code.
+ */
+int jack_port_set_name (jack_port_t *port, const char *port_name) JACK_OPTIONAL_WEAK_DEPRECATED_EXPORT;
+
+/**
+ * Modify a port's short name.  May NOT be called from a callback handling a server event.
+ * If the resulting full name (including the @a "client_name:" prefix) is
+ * longer than jack_port_name_size(), it will be truncated.
+ *
+ * @return 0 on success, otherwise a non-zero error code.
+ *
+ * This differs from jack_port_set_name() by triggering PortRename notifications to
+ * clients that have registered a port rename handler.
+ */
+int jack_port_rename (jack_client_t* client, jack_port_t *port, const char *port_name) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * Set @a alias as an alias for @a port.  May be called at any time.
+ * If the alias is longer than jack_port_name_size(), it will be truncated.
+ *
+ * After a successful call, and until JACK exits or
+ * @function jack_port_unset_alias() is called, @alias may be
+ * used as a alternate name for the port.
+ *
+ * Ports can have up to two aliases - if both are already
+ * set, this function will return an error.
+ *
+ * @return 0 on success, otherwise a non-zero error code.
+ */
+int jack_port_set_alias (jack_port_t *port, const char *alias) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * Remove @a alias as an alias for @a port.  May be called at any time.
+ *
+ * After a successful call, @a alias can no longer be
+ * used as a alternate name for the port.
+ *
+ * @return 0 on success, otherwise a non-zero error code.
+ */
+int jack_port_unset_alias (jack_port_t *port, const char *alias) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * Get any aliases known for @port.
+ *
+ * @return the number of aliases discovered for the port
+ */
+int jack_port_get_aliases (const jack_port_t *port, char* const aliases[2]) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * If @ref JackPortCanMonitor is set for this @a port, turn input
+ * monitoring on or off.  Otherwise, do nothing.
+ */
+int jack_port_request_monitor (jack_port_t *port, int onoff) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * If @ref JackPortCanMonitor is set for this @a port_name, turn input
+ * monitoring on or off.  Otherwise, do nothing.
+ *
+ * @return 0 on success, otherwise a non-zero error code.
+ *
+ * @see jack_port_name_size()
+ */
+int jack_port_request_monitor_by_name (jack_client_t *client,
+                                       const char *port_name, int onoff) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * If @ref JackPortCanMonitor is set for a port, this function turns
+ * on input monitoring if it was off, and turns it off if only one
+ * request has been made to turn it on.  Otherwise it does nothing.
+ *
+ * @return 0 on success, otherwise a non-zero error code
+ */
+int jack_port_ensure_monitor (jack_port_t *port, int onoff) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * @return TRUE if input monitoring has been requested for @a port.
+ */
+int jack_port_monitoring_input (jack_port_t *port) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * Establish a connection between two ports.
+ *
+ * When a connection exists, data written to the source port will
+ * be available to be read at the destination port.
+ *
+ * @pre The port types must be identical.
+ *
+ * @pre The @ref JackPortFlags of the @a source_port must include @ref
+ * JackPortIsOutput.
+ *
+ * @pre The @ref JackPortFlags of the @a destination_port must include
+ * @ref JackPortIsInput.
+ *
+ * @return 0 on success, EEXIST if the connection is already made,
+ * otherwise a non-zero error code
+ */
+int jack_connect (jack_client_t *client,
+                  const char *source_port,
+                  const char *destination_port) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * Remove a connection between two ports.
+ *
+ * @pre The port types must be identical.
+ *
+ * @pre The @ref JackPortFlags of the @a source_port must include @ref
+ * JackPortIsOutput.
+ *
+ * @pre The @ref JackPortFlags of the @a destination_port must include
+ * @ref JackPortIsInput.
+ *
+ * @return 0 on success, otherwise a non-zero error code
+ */
+int jack_disconnect (jack_client_t *client,
+                     const char *source_port,
+                     const char *destination_port) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * Perform the same function as jack_disconnect() using port handles
+ * rather than names.  This avoids the name lookup inherent in the
+ * name-based version.
+ *
+ * Clients connecting their own ports are likely to use this function,
+ * while generic connection clients (e.g. patchbays) would use
+ * jack_disconnect().
+ */
+int jack_port_disconnect (jack_client_t *client, jack_port_t *port) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * @return the maximum number of characters in a full JACK port name
+ * including the final NULL character.  This value is a constant.
+ *
+ * A port's full name contains the owning client name concatenated
+ * with a colon (:) followed by its short name and a NULL
+ * character.
+ */
+int jack_port_name_size(void) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * @return the maximum number of characters in a JACK port type name
+ * including the final NULL character.  This value is a constant.
+ */
+int jack_port_type_size(void) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * @return the buffersize of a port of type @arg port_type.
+ *
+ * this function may only be called in a buffer_size callback.
+ */
+size_t jack_port_type_get_buffer_size (jack_client_t *client, const char *port_type) JACK_WEAK_EXPORT;
+
+/*@}*/
+
+/**
+ * @defgroup LatencyFunctions Managing and determining latency
+ *
+ * The purpose of JACK's latency API is to allow clients to
+ * easily answer two questions:
+ *
+ * - How long has it been since the data read from a port arrived
+ *   at the edge of the JACK graph (either via a physical port
+ *   or being synthesized from scratch)?
+ *
+ * - How long will it be before the data written to a port arrives
+ *   at the edge of a JACK graph?
+
+ * To help answering these two questions, all JACK ports have two
+ * latency values associated with them, both measured in frames:
+ *
+ * <b>capture latency</b>: how long since the data read from
+ *                  the buffer of a port arrived at
+ *                  a port marked with JackPortIsTerminal.
+ *                  The data will have come from the "outside
+ *                  world" if the terminal port is also
+ *                  marked with JackPortIsPhysical, or
+ *                  will have been synthesized by the client
+ *                  that owns the terminal port.
+ *
+ * <b>playback latency</b>: how long until the data
+ *                   written to the buffer of port will reach a port
+ *                   marked with JackPortIsTerminal.
+ *
+ * Both latencies might potentially have more than one value
+ * because there may be multiple pathways to/from a given port
+ * and a terminal port. Latency is therefore generally
+ * expressed a min/max pair.
+ *
+ * In most common setups, the minimum and maximum latency
+ * are the same, but this design accommodates more complex
+ * routing, and allows applications (and thus users) to
+ * detect cases where routing is creating an anomalous
+ * situation that may either need fixing or more
+ * sophisticated handling by clients that care about
+ * latency.
+ *
+ * See also @ref jack_set_latency_callback for details on how
+ * clients that add latency to the signal path should interact
+ * with JACK to ensure that the correct latency figures are
+ * used.
+ * @{
+ */
+
+/**
+ * The port latency is zero by default. Clients that control
+ * physical hardware with non-zero latency should call this
+ * to set the latency to its correct value. Note that the value
+ * should include any systemic latency present "outside" the
+ * physical hardware controlled by the client. For example,
+ * for a client controlling a digital audio interface connected
+ * to an external digital converter, the latency setting should
+ * include both buffering by the audio interface *and* the converter.
+ *
+ * @deprecated This method will be removed in the next major
+ * release of JACK. It should not be used in new code, and should
+ * be replaced by a latency callback that calls @ref
+ * jack_port_set_latency_range().
+ */
+void jack_port_set_latency (jack_port_t *port, jack_nframes_t) JACK_OPTIONAL_WEAK_DEPRECATED_EXPORT;
+
+/**
+ * return the latency range defined by @a mode for
+ * @a port, in frames.
+ *
+ * See @ref LatencyFunctions for the definition of each latency value.
+ *
+ * This function is best used from callbacks, specifically the latency callback.
+ * Before a port is connected, this returns the default latency: zero.
+ * Therefore it only makes sense to call jack_port_get_latency_range() when
+ * the port is connected, and that gets signalled by the latency callback.
+ * See @ref jack_set_latency_callback() for details.
+ */
+void jack_port_get_latency_range (jack_port_t *port, jack_latency_callback_mode_t mode, jack_latency_range_t *range) JACK_WEAK_EXPORT;
+
+/**
+ * set the minimum and maximum latencies defined by
+ * @a mode for @a port, in frames.
+ *
+ * See @ref LatencyFunctions for the definition of each latency value.
+ *
+ * This function should ONLY be used inside a latency
+ * callback. The client should determine the current
+ * value of the latency using @ref jack_port_get_latency_range()
+ * (called using the same mode as @a mode)
+ * and then add some number of frames to that reflects
+ * latency added by the client.
+ *
+ * How much latency a client adds will vary
+ * dramatically. For most clients, the answer is zero
+ * and there is no reason for them to register a latency
+ * callback and thus they should never call this
+ * function.
+ *
+ * More complex clients that take an input signal,
+ * transform it in some way and output the result but
+ * not during the same process() callback will
+ * generally know a single constant value to add
+ * to the value returned by @ref jack_port_get_latency_range().
+ *
+ * Such clients would register a latency callback (see
+ * @ref jack_set_latency_callback) and must know what input
+ * ports feed which output ports as part of their
+ * internal state. Their latency callback will update
+ * the ports' latency values appropriately.
+ *
+ * A pseudo-code example will help. The @a mode argument to the latency
+ * callback will determine whether playback or capture
+ * latency is being set. The callback will use
+ * @ref jack_port_set_latency_range() as follows:
+ *
+ * \code
+ * jack_latency_range_t range;
+ * if (mode == JackPlaybackLatency) {
+ *  foreach input_port in (all self-registered port) {
+ *   jack_port_get_latency_range (port_feeding_input_port, JackPlaybackLatency, &range);
+ *   range.min += min_delay_added_as_signal_flows_from port_feeding to input_port;
+ *   range.max += max_delay_added_as_signal_flows_from port_feeding to input_port;
+ *   jack_port_set_latency_range (input_port, JackPlaybackLatency, &range);
+ *  }
+ * } else if (mode == JackCaptureLatency) {
+ *  foreach output_port in (all self-registered port) {
+ *   jack_port_get_latency_range (port_fed_by_output_port, JackCaptureLatency, &range);
+ *   range.min += min_delay_added_as_signal_flows_from_output_port_to_fed_by_port;
+ *   range.max += max_delay_added_as_signal_flows_from_output_port_to_fed_by_port;
+ *   jack_port_set_latency_range (output_port, JackCaptureLatency, &range);
+ *  }
+ * }
+ * \endcode
+ *
+ * In this relatively simple pseudo-code example, it is assumed that
+ * each input port or output is connected to only 1 output or input
+ * port respectively.
+ *
+ * If a port is connected to more than 1 other port, then the
+ * range.min and range.max values passed to @ref
+ * jack_port_set_latency_range() should reflect the minimum and
+ * maximum values across all connected ports.
+ *
+ * See the description of @ref jack_set_latency_callback for more
+ * information.
+ */
+void jack_port_set_latency_range (jack_port_t *port, jack_latency_callback_mode_t mode, jack_latency_range_t *range) JACK_WEAK_EXPORT;
+
+/**
+ * Request a complete recomputation of all port latencies. This
+ * can be called by a client that has just changed the internal
+ * latency of its port using  jack_port_set_latency
+ * and wants to ensure that all signal pathways in the graph
+ * are updated with respect to the values that will be returned
+ * by  jack_port_get_total_latency. It allows a client
+ * to change multiple port latencies without triggering a
+ * recompute for each change.
+ *
+ * @return zero for successful execution of the request. non-zero
+ *         otherwise.
+ */
+int jack_recompute_total_latencies (jack_client_t *client) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * @return the time (in frames) between data being available or
+ * delivered at/to a port, and the time at which it arrived at or is
+ * delivered to the "other side" of the port.  E.g. for a physical
+ * audio output port, this is the time between writing to the port and
+ * when the signal will leave the connector.  For a physical audio
+ * input port, this is the time between the sound arriving at the
+ * connector and the corresponding frames being readable from the
+ * port.
+ *
+ * @deprecated This method will be removed in the next major
+ * release of JACK. It should not be used in new code, and should
+ * be replaced by jack_port_get_latency_range() in any existing
+ * use cases.
+ */
+jack_nframes_t jack_port_get_latency (jack_port_t *port) JACK_OPTIONAL_WEAK_DEPRECATED_EXPORT;
+
+/**
+ * The maximum of the sum of the latencies in every
+ * connection path that can be drawn between the port and other
+ * ports with the @ref JackPortIsTerminal flag set.
+ *
+ * @deprecated This method will be removed in the next major
+ * release of JACK. It should not be used in new code, and should
+ * be replaced by jack_port_get_latency_range() in any existing
+ * use cases.
+ */
+jack_nframes_t jack_port_get_total_latency (jack_client_t *client,
+					    jack_port_t *port) JACK_OPTIONAL_WEAK_DEPRECATED_EXPORT;
+
+/**
+ * Request a complete recomputation of a port's total latency. This
+ * can be called by a client that has just changed the internal
+ * latency of its port using  jack_port_set_latency
+ * and wants to ensure that all signal pathways in the graph
+ * are updated with respect to the values that will be returned
+ * by  jack_port_get_total_latency.
+ *
+ * @return zero for successful execution of the request. non-zero
+ *         otherwise.
+ *
+ * @deprecated This method will be removed in the next major
+ * release of JACK. It should not be used in new code, and should
+ * be replaced by jack_recompute_total_latencies() in any existing
+ * use cases.
+ */
+int jack_recompute_total_latency (jack_client_t*, jack_port_t* port) JACK_OPTIONAL_WEAK_DEPRECATED_EXPORT;
+
+/*@}*/
+
+/**
+ * @defgroup PortSearching Looking up ports
+ * @{
+ */
+
+/**
+ * @param port_name_pattern A regular expression used to select
+ * ports by name.  If NULL or of zero length, no selection based
+ * on name will be carried out.
+ * @param type_name_pattern A regular expression used to select
+ * ports by type.  If NULL or of zero length, no selection based
+ * on type will be carried out.
+ * @param flags A value used to select ports by their flags.
+ * If zero, no selection based on flags will be carried out.
+ *
+ * @return a NULL-terminated array of ports that match the specified
+ * arguments.  The caller is responsible for calling jack_free() any
+ * non-NULL returned value.
+ *
+ * @see jack_port_name_size(), jack_port_type_size()
+ */
+const char ** jack_get_ports (jack_client_t *client,
+                              const char *port_name_pattern,
+                              const char *type_name_pattern,
+                              unsigned long flags) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * @return address of the jack_port_t named @a port_name.
+ *
+ * @see jack_port_name_size()
+ */
+jack_port_t * jack_port_by_name (jack_client_t *client, const char *port_name) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * @return address of the jack_port_t of a @a port_id.
+ */
+jack_port_t * jack_port_by_id (jack_client_t *client,
+                               jack_port_id_t port_id) JACK_OPTIONAL_WEAK_EXPORT;
+
+/*@}*/
+
+/**
+ * @defgroup TimeFunctions Handling time
+ * @{
+ *
+ * JACK time is in units of 'frames', according to the current sample rate.
+ * The absolute value of frame times is meaningless, frame times have meaning
+ * only relative to each other.
+ */
+
+/**
+ * @return the estimated time in frames that has passed since the JACK
+ * server began the current process cycle.
+ */
+jack_nframes_t jack_frames_since_cycle_start (const jack_client_t *) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * @return the estimated current time in frames.
+ * This function is intended for use in other threads (not the process
+ * callback).  The return value can be compared with the value of
+ * jack_last_frame_time to relate time in other threads to JACK time.
+ */
+jack_nframes_t jack_frame_time (const jack_client_t *) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * @return the precise time at the start of the current process cycle.
+ * This function may only be used from the process callback, and can
+ * be used to interpret timestamps generated by jack_frame_time() in
+ * other threads with respect to the current process cycle.
+ *
+ * This is the only jack time function that returns exact time:
+ * when used during the process callback it always returns the same
+ * value (until the next process callback, where it will return
+ * that value + nframes, etc).  The return value is guaranteed to be
+ * monotonic and linear in this fashion unless an xrun occurs.
+ * If an xrun occurs, clients must check this value again, as time
+ * may have advanced in a non-linear way (e.g. cycles may have been skipped).
+ */
+jack_nframes_t jack_last_frame_time (const jack_client_t *client) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * This function may only be used from the process callback.
+ * It provides the internal cycle timing information as used by
+ * most of the other time related functions. This allows the
+ * caller to map between frame counts and microseconds with full
+ * precision (i.e. without rounding frame times to integers),
+ * and also provides e.g. the microseconds time of the start of
+ * the current cycle directly (it has to be computed otherwise).
+ *
+ * If the return value is zero, the following information is
+ * provided in the variables pointed to by the arguments:
+ *
+ * current_frames: the frame time counter at the start of the
+ *                 current cycle, same as jack_last_frame_time().
+ * current_usecs:  the microseconds time at the start of the
+ *                 current cycle.
+ * next_usecs:     the microseconds time of the start of the next
+ *                 next cycle as computed by the DLL.
+ * period_usecs:   the current best estimate of the period time in
+ *                  microseconds.
+ *
+ * NOTES:
+ * 
+ * Because of the types used, all the returned values except period_usecs
+ * are unsigned. In computations mapping between frames and microseconds
+ * *signed* differences are required. The easiest way is to compute those
+ * separately and assign them to the appropriate signed variables,
+ * int32_t for frames and int64_t for usecs. See the implementation of
+ * jack_frames_to_time() and Jack_time_to_frames() for an example.
+ * 
+ * Unless there was an xrun, skipped cycles, or the current cycle is the
+ * first after freewheeling or starting Jack, the value of current_usecs
+ * will always be the value of next_usecs of the previous cycle.
+ *
+ * The value of period_usecs will in general NOT be exactly equal to
+ * the difference of next_usecs and current_usecs. This is because to
+ * ensure stability of the DLL and continuity of the mapping, a fraction
+ * of the loop error must be included in next_usecs. For an accurate
+ * mapping between frames and microseconds, the difference of next_usecs
+ * and current_usecs should be used, and not period_usecs.
+ *
+ * @return zero if OK, non-zero otherwise.
+ */
+int jack_get_cycle_times(const jack_client_t *client,
+                        jack_nframes_t *current_frames,
+                        jack_time_t    *current_usecs,
+                        jack_time_t    *next_usecs,
+                        float          *period_usecs) JACK_OPTIONAL_WEAK_EXPORT;
+                  
+/**
+ * @return the estimated time in microseconds of the specified frame time
+ */
+jack_time_t jack_frames_to_time(const jack_client_t *client, jack_nframes_t) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * @return the estimated time in frames for the specified system time.
+ */
+jack_nframes_t jack_time_to_frames(const jack_client_t *client, jack_time_t) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * @return return JACK's current system time in microseconds,
+ *         using the JACK clock source.
+ *
+ * The value returned is guaranteed to be monotonic, but not linear.
+ */
+jack_time_t jack_get_time(void) JACK_OPTIONAL_WEAK_EXPORT;
+
+/*@}*/
+
+/**
+ * @defgroup ErrorOutput Controlling error/information output
+ */
+/*@{*/
+
+/**
+ * Display JACK error message.
+ *
+ * Set via jack_set_error_function(), otherwise a JACK-provided
+ * default will print @a msg (plus a newline) to stderr.
+ *
+ * @param msg error message text (no newline at end).
+ */
+extern void (*jack_error_callback)(const char *msg) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * Set the @ref jack_error_callback for error message display.
+ * Set it to NULL to restore default_jack_error_callback function.
+ *
+ * The JACK library provides two built-in callbacks for this purpose:
+ * default_jack_error_callback() and silent_jack_error_callback().
+ */
+void jack_set_error_function (void (*func)(const char *)) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * Display JACK info message.
+ *
+ * Set via jack_set_info_function(), otherwise a JACK-provided
+ * default will print @a msg (plus a newline) to stdout.
+ *
+ * @param msg info message text (no newline at end).
+ */
+extern void (*jack_info_callback)(const char *msg) JACK_OPTIONAL_WEAK_EXPORT;
+
+/**
+ * Set the @ref jack_info_callback for info message display.
+ * Set it to NULL to restore default_jack_info_callback function.
+ *
+ * The JACK library provides two built-in callbacks for this purpose:
+ * default_jack_info_callback() and silent_jack_info_callback().
+ */
+void jack_set_info_function (void (*func)(const char *)) JACK_OPTIONAL_WEAK_EXPORT;
+
+/*@}*/
+
+/**
+ * The free function to be used on memory returned by jack_port_get_connections,
+ * jack_port_get_all_connections, jack_get_ports and jack_get_internal_client_name functions.
+ * This is MANDATORY on Windows when otherwise all nasty runtime version related crashes can occur.
+ * Developers are strongly encouraged to use this function instead of the standard "free" function in new code.
+ *
+ * @param ptr the memory pointer to be deallocated.
+ */
+void jack_free(void* ptr) JACK_OPTIONAL_WEAK_EXPORT;
+
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __jack_h__ */