Docs » Autodocs » audio.device » ADCMD_SETPREC
ADCMD_SETPREC -- set the allocation precedence for audio channels
ADCMD_SETPREC is a command for multiple audio channels. For each
selected channel (io_Unit), if the allocation key (ioa_AllocKey) is
correct, ADCMD_SETPREC sets the allocation precedence to a new value
(ln_Pri) and checks if there are allocation requests (ADCMD_ALLOCATE)
waiting for the channel which now have higher precedence; otherwise,
ADCMD_SETPREC returns an error (ADIOERR_NOALLOCATION). ADCMD_SETPREC
is synchronous and only replies (mn_ReplyPort) if the quick flag
(IOF_QUICK) is clear. Do not use ADCMD_SETPREC in interrupt code.
ln_Pri - new allocation precedence (-128 thru 127)
mn_ReplyPort- pointer to message port that receives I/O request
if the quick flag (IOF_QUICK) is clear
io_Device - pointer to device node, must be set by (or copied from
I/O block set by) OpenDevice function
io_Unit - bit map of channels to set precedence (bits 0 thru 3
correspond to channels 0 thru 3)
io_Command - command number for ADCMD_SETPREC
io_Flags - flags, must be cleared if not used:
IOF_QUICK - (CLEAR) reply I/O request
ioa_AllocKey- allocation key, must be set by (or copied from I/O block
set by) OpenDevice function or ADCMD_ALLOCATE command
io_Unit - bit map of channels that successfully set precedence
(bits 0 thru 3 correspond to channels 0 thru 3)
io_Error - error number:
0 - no error
ADIOERR_NOALLOCATION - allocation key (ioa_AllocKey)
does not match key for channel
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