The string interface enables application control of media devices using textual string commands. String commands are passed to the media control interface through the mciSendString function. Return information from string commands is converted to string format and returned in the pszReturnString parameter of mciSendString.

Not all functions available through the procedural interface, mciSendCommand, are available through the string interface. In general, operations that return complex data structures, such as a CD table of contents, are available only through the procedural interface. Operations that cause asynchronous responses to be generated, such as cue point and position advise, can be invoked from the string interface; however, their responses are returned to window procedures.

The keywords WAIT and NOTIFY are global keywords and are available for all commands except some system commands. As with the procedural interface, the default time base is MMTIME. The multimedia string parser is case insensitive.

Command Format

The string format is:

COMMAND ÄÄÄ object ÄÄÄÂÄÄÄÄÄÄÄÄÄÄÄÄÂÄÄÂÄÄÄÄÄÄÄÄÄÄÂÄÄ´
                      ÀÄ keywords ÄÙ  ÃÄ WAIT ÄÄÄ´
                                      ÀÄ NOTIFY ÄÙ

object         = device type | device name | filename | alias
keywords       = command-specific keywords
WAIT | NOTIFY  = standard OS/2 multimedia definitions

The object associated with a media control interface command can be one of the following:

• Device type - The default device of a given type. The possible types of controllable devices include the following:

  Device

  Description
  videotape
  Videotape player or recorder
  videodisc
  Videodisc player
  cdaudio
  CD-ROM device that supports standard compact disc playback
  waveaudio
  Device that supports digital audio files
  sequencer
  Device that supports MIDI files
  digitalvideo
  Device that supports audio/video files, either hardware-assisted or software motion video only
  If you have multiple devices of the same type, the Multimedia Setup program allows you to decide which device should be the default for that type.
  
  Device name - A name of a particular device. Device names are of the form DevicetypeNN, where Devicetype is one of the device types given above, and NN is a value (01, 02,...) indicating which device of that type is to be controlled.
  
  Filename - The name of a file to be opened or controlled. When a filename is opened, OS/2 multimedia first examines the file's extension, then its type, to determine which device is associated to the file.
  
  Alias - A string that was specified on a previous OPEN command. This string can then be used as the object name in subsequent commands.

  The only exception to the above command format is MASTERAUDIO, which does not require an object associated with the command. The format for MASTERAUDIO is:

  MASTERAUDIO ÄÄÄÄ keywords ÄÄÄÂÄÄÄÄÄÄÄÄÂÄÄÄÄÄ´                             ÀÄ WAIT ÄÙ
  

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