cd.device/CD_QCODELSN

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 NAME
 CD_QCODELSN -- Report current disk position.
 IO REQUEST
 io_Device preset by the call to OpenDevice()
 io_Unit preset by the call to OpenDevice()
 io_Command CD_QCODELSN
 io_Data pointer to QCode structure
 io_Length 0 - MUST be zero (for future compatability)
 RESULTS
 io_Error 0 for success, or an error code as defined in
 <devices/cd.h>
 FUNCTION
 This command reports current subcode Q channel time information. This
 command only returns data when CD Audio is playing (or paused). At
 any other time, an error is returned. The Q-Code packet consists of:
 struct QCode {
 UBYTE CtlAdr; /* Data type / QCode type */
 UBYTE Track; /* Track number */
 UBYTE Index; /* Track subindex number */
 UBYTE Zero; /* The "Zero" byte of Q-Code packet */
 union LSNMSF TrackPosition; /* Position from start of track */
 union LSNMSF DiskPosition; /* Position from start of disk */
 };
 EXAMPLE
 struct QCode qcode;
 ior->io_Command = CD_QCODELSN; /* Retrieve TOC information */
 ior->io_Length = 0; /* MUST be zero */
 ior->io_Data = (APTR)qcode; /* Here's where we want it */
 DoIO (ior);
 if (!ior->io_Error) { /* Command succeeded */
 printf("Current position is: %ldn", qcode.DiskPosition.LSN);
 }
 NOTES
 This function may not return immediately. It may take several frames
 to pass by before a valid Q-Code packet can be returned. Use SendIO()
 and CheckIO() if response time is critical, and the information is
 not.
 BUGS
 SEE ALSO
 CD_PLAYMSF, CD_PLAYLSN, CD_PLAYTRACK, <devices/cd.h>

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