cue
The cue
command prepares for playing or recording. Digital-video, VCR, and
waveform-audio devices recognize this command.
wsprintf(lpstrCommand, "cue %s %s %s",
lpszDeviceID, lpszInOutTo,
lpszFlags);
Parameters
lpszDeviceID
Identifier of
an MCI device. This identifier or alias is assigned when the device is opened.
lpszInOutTo
Flag that
prepares a device for playing or recording. The following table lists device
types that recognize the cue command and the flags used by each type:
|
digitalvideo |
input |
output |
|
vcr |
from position |
preroll |
|
waveaudio |
input |
output |
The following
table lists the flags that can be specified in the lpszInOutTo parameter
and their meanings:
|
from position
|
Indicates
where to start. |
|
input |
Prepares
for recording. For digital-video devices, this flag can be omitted if the
current presentation source is already the external input. |
|
noshow |
Prepares
for playing a frame without displaying it. When this flag is specified, the
display continues to show the image in the frame buffer even though its corresponding
frame is not the current position. A subsequent cue command without
this flag and without the to flag displays the current frame. |
|
output |
Prepares
for playing. If neither input nor output is specified, the default
setting is output . |
|
preroll |
Moves the
preroll distance from the in-point. The in-point is the current
position, or the position specified by the from flag. |
|
reverse |
Indicates
play direction is in reverse (backward). |
|
to position |
Moves the
workspace to the specified position. For VCR devices, this flag indicates
where to stop. |
lpszFlags
Can be
wait , notify , or both. For digital-video and VCR devices, test can also
be specified. For more information about these flags, see The Wait, Notify,
and Test Flags.
Return Values
Returns zero
if successful or an error otherwise.
Remarks
Although it
is not necessary, issuing the cue command before playing or recording on
some devices might reduce the delay before the device starts the action.
This command
fails if playing or recording is in progress or if the device is paused.
When cueing
for playback (using cue output ), issuing the play command with the from ,
to , or reverse flag cancels the cue command.
When cueing
for recording (using cue input ), issuing the record command with the from ,
to , or initialize flag cancels the cue command.
The following
command prepares the mysound device for recording:
cue mysound input
See Also