SCSIMsgIn
short * message; message value as defined by ANSI's SCSI
documentation
SCSIMsgIn gets a message from the external drive. * message is in the low-order byte of the message parameter.
Returns: an error code indicating success or failure of the function. It will be one of:
noErr (0) No error
scArbNBErr (3) Arbitration failure during SCSIGet; bus busy
scMgrBusyErr (7) SCSI Manager already occupied when SCSIGet was called
scSequenceErr (8) Operation out of sequence
scBusTOErr (9) Bus timeout before data ready on blind read or write
scComplPhaseErr (10) Bus not in Status phase; SCSIComplete call failed
Notes: Message values are listed in SCSI documentation from the American
National Standards Institute. This routine leaves the Attention bus line
undisturbed if it is already asserted.