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Sequencer Port Interface
MIDI Sequencer

Macros

#define SND_SEQ_PORT_SYSTEM_TIMER   0
#define SND_SEQ_PORT_SYSTEM_ANNOUNCE   1
#define SND_SEQ_PORT_CAP_READ   (1<<0)
#define SND_SEQ_PORT_CAP_WRITE   (1<<1)
#define SND_SEQ_PORT_CAP_SYNC_READ   (1<<2)
#define SND_SEQ_PORT_CAP_SYNC_WRITE   (1<<3)
#define SND_SEQ_PORT_CAP_DUPLEX   (1<<4)
#define SND_SEQ_PORT_CAP_SUBS_READ   (1<<5)
#define SND_SEQ_PORT_CAP_SUBS_WRITE   (1<<6)
#define SND_SEQ_PORT_CAP_NO_EXPORT   (1<<7)
#define SND_SEQ_PORT_TYPE_SPECIFIC   (1<<0)
#define SND_SEQ_PORT_TYPE_MIDI_GENERIC   (1<<1)
#define SND_SEQ_PORT_TYPE_MIDI_GM   (1<<2)
#define SND_SEQ_PORT_TYPE_MIDI_GS   (1<<3)
#define SND_SEQ_PORT_TYPE_MIDI_XG   (1<<4)
#define SND_SEQ_PORT_TYPE_MIDI_MT32   (1<<5)
#define SND_SEQ_PORT_TYPE_MIDI_GM2   (1<<6)
#define SND_SEQ_PORT_TYPE_SYNTH   (1<<10)
#define SND_SEQ_PORT_TYPE_DIRECT_SAMPLE   (1<<11)
#define SND_SEQ_PORT_TYPE_SAMPLE   (1<<12)
#define SND_SEQ_PORT_TYPE_HARDWARE   (1<<16)
#define SND_SEQ_PORT_TYPE_SOFTWARE   (1<<17)
#define SND_SEQ_PORT_TYPE_SYNTHESIZER   (1<<18)
#define SND_SEQ_PORT_TYPE_PORT   (1<<19)
#define SND_SEQ_PORT_TYPE_APPLICATION   (1<<20)
#define snd_seq_port_info_alloca(ptr)   __snd_alloca(ptr, snd_seq_port_info)

Typedefs

typedef struct _snd_seq_port_info snd_seq_port_info_t

Functions

size_t snd_seq_port_info_sizeof (void)
 get size of snd_seq_port_info_t
int snd_seq_port_info_malloc (snd_seq_port_info_t **ptr)
 allocate an empty snd_seq_port_info_t using standard malloc
void snd_seq_port_info_free (snd_seq_port_info_t *ptr)
 frees a previously allocated snd_seq_port_info_t
void snd_seq_port_info_copy (snd_seq_port_info_t *dst, const snd_seq_port_info_t *src)
 copy one snd_seq_port_info_t to another
int snd_seq_port_info_get_client (const snd_seq_port_info_t *info)
 Get client id of a port_info container.
int snd_seq_port_info_get_port (const snd_seq_port_info_t *info)
 Get port id of a port_info container.
const snd_seq_addr_tsnd_seq_port_info_get_addr (const snd_seq_port_info_t *info)
 Get client/port address of a port_info container.
const char * snd_seq_port_info_get_name (const snd_seq_port_info_t *info)
 Get the name of a port_info container.
unsigned int snd_seq_port_info_get_capability (const snd_seq_port_info_t *info)
 Get the capability bits of a port_info container.
unsigned int snd_seq_port_info_get_type (const snd_seq_port_info_t *info)
 Get the type bits of a port_info container.
int snd_seq_port_info_get_midi_channels (const snd_seq_port_info_t *info)
 Get the midi channels of a port_info container.
int snd_seq_port_info_get_midi_voices (const snd_seq_port_info_t *info)
 Get the midi voices of a port_info container.
int snd_seq_port_info_get_synth_voices (const snd_seq_port_info_t *info)
 Get the synth voices of a port_info container.
int snd_seq_port_info_get_read_use (const snd_seq_port_info_t *info)
 Get the number of read subscriptions of a port_info container.
int snd_seq_port_info_get_write_use (const snd_seq_port_info_t *info)
 Get the number of write subscriptions of a port_info container.
int snd_seq_port_info_get_port_specified (const snd_seq_port_info_t *info)
 Get the port-specified mode of a port_info container.
int snd_seq_port_info_get_timestamping (const snd_seq_port_info_t *info)
 Get the time-stamping mode of the given port in a port_info container.
int snd_seq_port_info_get_timestamp_real (const snd_seq_port_info_t *info)
 Get whether the time-stamping of the given port is real-time mode.
int snd_seq_port_info_get_timestamp_queue (const snd_seq_port_info_t *info)
 Get the queue id to update timestamps.
void snd_seq_port_info_set_client (snd_seq_port_info_t *info, int client)
 Set the client id of a port_info container.
void snd_seq_port_info_set_port (snd_seq_port_info_t *info, int port)
 Set the port id of a port_info container.
void snd_seq_port_info_set_addr (snd_seq_port_info_t *info, const snd_seq_addr_t *addr)
 Set the client/port address of a port_info container.
void snd_seq_port_info_set_name (snd_seq_port_info_t *info, const char *name)
 Set the name of a port_info container.
void snd_seq_port_info_set_capability (snd_seq_port_info_t *info, unsigned int capability)
 set the capability bits of a port_info container
void snd_seq_port_info_set_type (snd_seq_port_info_t *info, unsigned int type)
 Get the type bits of a port_info container.
void snd_seq_port_info_set_midi_channels (snd_seq_port_info_t *info, int channels)
 set the midi channels of a port_info container
void snd_seq_port_info_set_midi_voices (snd_seq_port_info_t *info, int voices)
 set the midi voices of a port_info container
void snd_seq_port_info_set_synth_voices (snd_seq_port_info_t *info, int voices)
 set the synth voices of a port_info container
void snd_seq_port_info_set_port_specified (snd_seq_port_info_t *info, int val)
 Set the port-specified mode of a port_info container.
void snd_seq_port_info_set_timestamping (snd_seq_port_info_t *info, int enable)
 Set the time-stamping mode of the given port.
void snd_seq_port_info_set_timestamp_real (snd_seq_port_info_t *info, int realtime)
 Set whether the timestime is updated in the real-time mode.
void snd_seq_port_info_set_timestamp_queue (snd_seq_port_info_t *info, int queue)
 Set the queue id for timestamping.
int snd_seq_create_port (snd_seq_t *handle, snd_seq_port_info_t *info)
 create a sequencer port on the current client
int snd_seq_delete_port (snd_seq_t *handle, int port)
 delete a sequencer port on the current client
int snd_seq_get_port_info (snd_seq_t *handle, int port, snd_seq_port_info_t *info)
 obtain the information of a port on the current client
int snd_seq_get_any_port_info (snd_seq_t *handle, int client, int port, snd_seq_port_info_t *info)
 obtain the information of a port on an arbitrary client
int snd_seq_set_port_info (snd_seq_t *handle, int port, snd_seq_port_info_t *info)
 set the information of a port on the current client
int snd_seq_query_next_port (snd_seq_t *handle, snd_seq_port_info_t *info)
 query the next matching port

Detailed Description

Sequencer Port Interface


Macro Definition Documentation

#define SND_SEQ_PORT_CAP_DUPLEX   (1<<4)

allow read/write duplex

#define SND_SEQ_PORT_CAP_NO_EXPORT   (1<<7)

routing not allowed

#define SND_SEQ_PORT_CAP_READ   (1<<0)

port capabilities (32 bits) readable from this port

#define SND_SEQ_PORT_CAP_SUBS_READ   (1<<5)

allow read subscription

#define SND_SEQ_PORT_CAP_SUBS_WRITE   (1<<6)

allow write subscription

#define SND_SEQ_PORT_CAP_SYNC_READ   (1<<2)

allow read subscriptions

#define SND_SEQ_PORT_CAP_SYNC_WRITE   (1<<3)

allow write subscriptions

#define SND_SEQ_PORT_CAP_WRITE   (1<<1)

writable to this port

#define snd_seq_port_info_alloca (   ptr)    __snd_alloca(ptr, snd_seq_port_info)

allocate a snd_seq_port_info_t container on stack

#define SND_SEQ_PORT_SYSTEM_ANNOUNCE   1

system announce port

#define SND_SEQ_PORT_SYSTEM_TIMER   0

known port numbers system timer port

#define SND_SEQ_PORT_TYPE_APPLICATION   (1<<20)

This port belongs to an application, such as a sequencer or editor.

#define SND_SEQ_PORT_TYPE_DIRECT_SAMPLE   (1<<11)

Instruments can be downloaded to this port (with SND_SEQ_EVENT_INSTR_xxx messages sent directly).

#define SND_SEQ_PORT_TYPE_HARDWARE   (1<<16)

This port is implemented in hardware.

#define SND_SEQ_PORT_TYPE_MIDI_GENERIC   (1<<1)

This port understands MIDI messages.

#define SND_SEQ_PORT_TYPE_MIDI_GM   (1<<2)

This port is compatible with the General MIDI specification.

#define SND_SEQ_PORT_TYPE_MIDI_GM2   (1<<6)

This port is compatible with the General MIDI 2 specification.

#define SND_SEQ_PORT_TYPE_MIDI_GS   (1<<3)

This port is compatible with the Roland GS standard.

#define SND_SEQ_PORT_TYPE_MIDI_MT32   (1<<5)

This port is compatible with the Roland MT-32.

#define SND_SEQ_PORT_TYPE_MIDI_XG   (1<<4)

This port is compatible with the Yamaha XG specification.

#define SND_SEQ_PORT_TYPE_PORT   (1<<19)

This port may connect to other devices (whose characteristics are not known).

#define SND_SEQ_PORT_TYPE_SAMPLE   (1<<12)

Instruments can be downloaded to this port (with SND_SEQ_EVENT_INSTR_xxx messages sent directly or through a queue).

#define SND_SEQ_PORT_TYPE_SOFTWARE   (1<<17)

This port is implemented in software.

#define SND_SEQ_PORT_TYPE_SPECIFIC   (1<<0)

Messages sent from/to this port have device-specific semantics.

#define SND_SEQ_PORT_TYPE_SYNTH   (1<<10)

This port understands SND_SEQ_EVENT_SAMPLE_xxx messages (these are not MIDI messages).

#define SND_SEQ_PORT_TYPE_SYNTHESIZER   (1<<18)

Messages sent to this port will generate sounds.


Typedef Documentation

typedef struct _snd_seq_port_info snd_seq_port_info_t

port information container


Function Documentation

int snd_seq_create_port ( snd_seq_t seq,
snd_seq_port_info_t port 
)

create a sequencer port on the current client

Parameters:
seqsequencer handle
portport information for the new port
Returns:
0 on success otherwise a negative error code

Creates a sequencer port on the current client. The attributes of created port is specified in info argument.

The client field in info argument is overwritten with the current client id. The port id to be created can be specified via snd_seq_port_info_set_port_specified. You can get the created port id by reading the port pointer via snd_seq_port_info_get_port.

Each port has the capability bit-masks to specify the access capability of the port from other clients. The capability bit flags are defined as follows:

Each port has also the type bitmasks defined as follows:

A port may contain specific midi channels, midi voices and synth voices. These values could be zero as default.

See also:
snd_seq_delete_port(), snd_seq_get_port_info(), snd_seq_create_simple_port()
int snd_seq_delete_port ( snd_seq_t seq,
int  port 
)

delete a sequencer port on the current client

Parameters:
seqsequencer handle
portport to be deleted
Returns:
0 on success otherwise a negative error code

Deletes the existing sequencer port on the current client.

See also:
snd_seq_create_port(), snd_seq_delete_simple_port()
int snd_seq_get_any_port_info ( snd_seq_t seq,
int  client,
int  port,
snd_seq_port_info_t info 
)

obtain the information of a port on an arbitrary client

Parameters:
seqsequencer handle
clientclient id to get
portport id to get
infopointer information returns
Returns:
0 on success otherwise a negative error code
See also:
snd_seq_get_port_info()
int snd_seq_get_port_info ( snd_seq_t seq,
int  port,
snd_seq_port_info_t info 
)

obtain the information of a port on the current client

Parameters:
seqsequencer handle
portport id to get
infopointer information returns
Returns:
0 on success otherwise a negative error code
See also:
snd_seq_create_port(), snd_seq_get_any_port_info(), snd_seq_set_port_info(), snd_seq_query_next_port()
void snd_seq_port_info_copy ( snd_seq_port_info_t dst,
const snd_seq_port_info_t src 
)

copy one snd_seq_port_info_t to another

Parameters:
dstpointer to destination
srcpointer to source
void snd_seq_port_info_free ( snd_seq_port_info_t obj)

frees a previously allocated snd_seq_port_info_t

Parameters:
objpointer to object to free
const snd_seq_addr_t* snd_seq_port_info_get_addr ( const snd_seq_port_info_t info)

Get client/port address of a port_info container.

Parameters:
infoport_info container
Returns:
client/port address pointer
See also:
snd_seq_get_port_info(), snd_seq_port_info_set_addr()
unsigned int snd_seq_port_info_get_capability ( const snd_seq_port_info_t info)

Get the capability bits of a port_info container.

Parameters:
infoport_info container
Returns:
capability bits
See also:
snd_seq_get_port_info(), snd_seq_port_info_set_capability()
int snd_seq_port_info_get_client ( const snd_seq_port_info_t info)

Get client id of a port_info container.

Parameters:
infoport_info container
Returns:
client id
See also:
snd_seq_get_port_info(), snd_seq_port_info_set_client()
int snd_seq_port_info_get_midi_channels ( const snd_seq_port_info_t info)

Get the midi channels of a port_info container.

Parameters:
infoport_info container
Returns:
number of midi channels (default 0)
See also:
snd_seq_get_port_info(), snd_seq_port_info_set_midi_channels()
int snd_seq_port_info_get_midi_voices ( const snd_seq_port_info_t info)

Get the midi voices of a port_info container.

Parameters:
infoport_info container
Returns:
number of midi voices (default 0)
See also:
snd_seq_get_port_info(), snd_seq_port_info_set_midi_voices()
const char* snd_seq_port_info_get_name ( const snd_seq_port_info_t info)

Get the name of a port_info container.

Parameters:
infoport_info container
Returns:
name string
See also:
snd_seq_get_port_info(), snd_seq_port_info_set_name()
int snd_seq_port_info_get_port ( const snd_seq_port_info_t info)

Get port id of a port_info container.

Parameters:
infoport_info container
Returns:
port id
See also:
snd_seq_get_port_info(), snd_seq_port_info_set_port()
int snd_seq_port_info_get_port_specified ( const snd_seq_port_info_t info)

Get the port-specified mode of a port_info container.

Parameters:
infoport_info container
Returns:
1 if port id is specified at creation
See also:
snd_seq_get_port_info(), snd_seq_port_info_set_port_specified()
int snd_seq_port_info_get_read_use ( const snd_seq_port_info_t info)

Get the number of read subscriptions of a port_info container.

Parameters:
infoport_info container
Returns:
number of read subscriptions
See also:
snd_seq_get_port_info()
int snd_seq_port_info_get_synth_voices ( const snd_seq_port_info_t info)

Get the synth voices of a port_info container.

Parameters:
infoport_info container
Returns:
number of synth voices (default 0)
See also:
snd_seq_get_port_info(), snd_seq_port_info_set_synth_voices()
int snd_seq_port_info_get_timestamp_queue ( const snd_seq_port_info_t info)

Get the queue id to update timestamps.

Parameters:
infoport_info container
Returns:
the queue id to get the timestamps
See also:
snd_seq_get_port_info(), snd_seq_port_info_set_timestamp_queue()
int snd_seq_port_info_get_timestamp_real ( const snd_seq_port_info_t info)

Get whether the time-stamping of the given port is real-time mode.

Parameters:
infoport_info container
Returns:
1 if the time-stamping is in the real-time mode
See also:
snd_seq_get_port_info(), snd_seq_port_info_set_timestamp_real()
int snd_seq_port_info_get_timestamping ( const snd_seq_port_info_t info)

Get the time-stamping mode of the given port in a port_info container.

Parameters:
infoport_info container
Returns:
1 if the port updates timestamps of incoming events
See also:
snd_seq_get_port_info(), snd_seq_port_info_set_timestamping()
unsigned int snd_seq_port_info_get_type ( const snd_seq_port_info_t info)

Get the type bits of a port_info container.

Parameters:
infoport_info container
Returns:
port type bits
See also:
snd_seq_get_port_info(), snd_seq_port_info_set_type()
int snd_seq_port_info_get_write_use ( const snd_seq_port_info_t info)

Get the number of write subscriptions of a port_info container.

Parameters:
infoport_info container
Returns:
number of write subscriptions
See also:
snd_seq_get_port_info()
int snd_seq_port_info_malloc ( snd_seq_port_info_t **  ptr)

allocate an empty snd_seq_port_info_t using standard malloc

Parameters:
ptrreturned pointer
Returns:
0 on success otherwise negative error code
void snd_seq_port_info_set_addr ( snd_seq_port_info_t info,
const snd_seq_addr_t addr 
)

Set the client/port address of a port_info container.

Parameters:
infoport_info container
addrclient/port address
See also:
snd_seq_get_port_info(), snd_seq_port_info_get_addr()
void snd_seq_port_info_set_capability ( snd_seq_port_info_t info,
unsigned int  capability 
)

set the capability bits of a port_info container

Parameters:
infoport_info container
capabilitycapability bits
See also:
snd_seq_get_port_info(), snd_seq_port_info_get_capability()
void snd_seq_port_info_set_client ( snd_seq_port_info_t info,
int  client 
)

Set the client id of a port_info container.

Parameters:
infoport_info container
clientclient id
See also:
snd_seq_get_port_info(), snd_seq_port_info_get_client()
void snd_seq_port_info_set_midi_channels ( snd_seq_port_info_t info,
int  channels 
)

set the midi channels of a port_info container

Parameters:
infoport_info container
channelsmidi channels (default 0)
See also:
snd_seq_get_port_info(), snd_seq_port_info_get_midi_channels()
void snd_seq_port_info_set_midi_voices ( snd_seq_port_info_t info,
int  voices 
)

set the midi voices of a port_info container

Parameters:
infoport_info container
voicesmidi voices (default 0)
See also:
snd_seq_get_port_info(), snd_seq_port_info_get_midi_voices()
void snd_seq_port_info_set_name ( snd_seq_port_info_t info,
const char *  name 
)

Set the name of a port_info container.

Parameters:
infoport_info container
namename string
See also:
snd_seq_get_port_info(), snd_seq_port_info_get_name()
void snd_seq_port_info_set_port ( snd_seq_port_info_t info,
int  port 
)

Set the port id of a port_info container.

Parameters:
infoport_info container
portport id
See also:
snd_seq_get_port_info(), snd_seq_port_info_get_port()
void snd_seq_port_info_set_port_specified ( snd_seq_port_info_t info,
int  val 
)

Set the port-specified mode of a port_info container.

Parameters:
infoport_info container
valnon-zero if specifying the port id at creation
See also:
snd_seq_get_port_info(), snd_seq_port_info_get_port_specified()
void snd_seq_port_info_set_synth_voices ( snd_seq_port_info_t info,
int  voices 
)

set the synth voices of a port_info container

Parameters:
infoport_info container
voicessynth voices (default 0)
See also:
snd_seq_get_port_info(), snd_seq_port_info_get_synth_voice()
void snd_seq_port_info_set_timestamp_queue ( snd_seq_port_info_t info,
int  queue 
)

Set the queue id for timestamping.

Parameters:
infoport_info container
queuethe queue id to get timestamps
See also:
snd_seq_get_port_info(), snd_seq_port_info_get_timestamp_queue()
void snd_seq_port_info_set_timestamp_real ( snd_seq_port_info_t info,
int  enable 
)

Set whether the timestime is updated in the real-time mode.

Parameters:
infoport_info container
enablenon-zero if updating the timestamps in real-time mode
See also:
snd_seq_get_port_info(), snd_seq_port_info_get_timestamp_real()
void snd_seq_port_info_set_timestamping ( snd_seq_port_info_t info,
int  enable 
)

Set the time-stamping mode of the given port.

Parameters:
infoport_info container
enablenon-zero if updating the timestamps of incoming events
See also:
snd_seq_get_port_info(), snd_seq_port_info_get_timestamping()
void snd_seq_port_info_set_type ( snd_seq_port_info_t info,
unsigned int  type 
)

Get the type bits of a port_info container.

Parameters:
infoport_info container
typeport type bits
See also:
snd_seq_get_port_info(), snd_seq_port_info_get_type()
size_t snd_seq_port_info_sizeof ( void  )

get size of snd_seq_port_info_t

Returns:
size in bytes
int snd_seq_query_next_port ( snd_seq_t seq,
snd_seq_port_info_t info 
)

query the next matching port

Parameters:
seqsequencer handle
infoquery pattern and result

Queries the next matching port on the client specified in info argument. The search begins at the next port specified in port field of info argument. For finding the first port at a certain client, give -1.

If a matching port is found, its attributes are stored on info and function returns zero. Otherwise, a negative error code is returned.

See also:
snd_seq_get_port_info()
int snd_seq_set_port_info ( snd_seq_t seq,
int  port,
snd_seq_port_info_t info 
)

set the information of a port on the current client

Parameters:
seqsequencer handle
portport to be set
infoport information to be set
Returns:
0 on success otherwise a negative error code
See also:
snd_seq_set_port_info()