# Creating & manipulating clients

## Functions

jack_client_t * | jack_client_open (const char *client_name, jack_options_t options, jack_status_t *status,...)
jack_client_t * | jack_client_new (const char *client_name)
int | jack_client_close (jack_client_t *client)
int | jack_client_name_size (void)
char * | jack_get_client_name (jack_client_t *client)
int | jack_internal_client_new (const char *client_name, const char *load_name, const char *load_init)
void | jack_internal_client_close (const char *client_name)
int | jack_activate (jack_client_t *client)
int | jack_deactivate (jack_client_t *client)
pthread_t | jack_client_thread_id (jack_client_t *)

## Detailed Description

Note: More documentation can be found in jack/types.h.

## Function Documentation

int jack_activate | ( | jack_client_t * | client | ) |

Tell the Jack server that the program is ready to start processing audio.

Returns:
  0 on success, otherwise a non-zero error code

Referenced by jack_initialize(), and main().

int jack_client_close | ( | jack_client_t * | client | ) |

Disconnects an external client from a JACK server.

Returns:
  0 on success, otherwise a non-zero error code

Referenced by main().

int jack_client_name_size | ( | void |  | ) |

Returns:
  the maximum number of characters in a JACK client name including the final NULL character. This value is a constant.

jack_client_t* jack_client_new | ( | const char * | client_name | ) |

THIS FUNCTION IS DEPRECATED AND SHOULD NOT BE USED IN NEW JACK CLIENTS

jack_client_t* jack_client_open | ( | const char * | client_name,
|  | jack_options_t | options,
|  | jack_status_t * | status,
|  |  | ... |
| ) |  |  |

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.

Parameters:

  | client_name | of at most jack_client_name_size() characters. The name scope is local to each server. Unless forbidden by the JackUseExactName option, the server will modify this name to create a unique variant, if needed.
  | options | formed by OR-ing together JackOptions bits. Only the JackOpenOptions bits are allowed.
  | 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 JackStatus bits.

Optional parameters: depending on corresponding [options bits] additional parameters may follow status (in this order).

- [JackServerName] (char *) server_name 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.

Returns:
  Opaque client handle if successful. If this is NULL, the open operation failed, *status includes JackFailure and the caller is not a JACK client.

Referenced by main().

pthread_t jack_client_thread_id | ( | jack_client_t * |  | ) |

Returns:
  the pthread ID of the thread running the JACK client side code.

int jack_deactivate | ( | jack_client_t * | client | ) |

Tell the Jack server to remove this client from the process graph. Also, disconnect all ports belonging to it, since inactive clients have no port connections.

Returns:
  0 on success, otherwise a non-zero error code

char* jack_get_client_name | ( | jack_client_t * | client | ) |

Returns:
  pointer to actual client name. This is useful when JackUseExactName is not specified on open and JackNameNotUnique status was returned. In that case, the actual name will differ from the client_name requested.

Referenced by main().

void jack_internal_client_close | ( | const char * | client_name | ) |

Remove an internal client from a JACK server.

Deprecated:
  Please use jack_internal_client_load().

int jack_internal_client_new | ( | const char * | client_name,
|  | const char * | load_name,
|  | const char * | load_init |
| ) |  |  |

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().

Parameters:

  | client_name | of at most jack_client_name_size() characters.
  | load_name | of a shared object file containing the code for the new client.
  | load_init | an arbitary string passed to the jack_initialize() routine of the new client (may be NULL).

Returns:
  0 if successful.