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play
The play command starts playing a device. CD audio, digital-video, MIDI sequencer,
videodisc, VCR, and waveform-audio devices recognize this command.
wsprintf(lpstrCommand, "play %s %s %s", lpszDeviceID, lpszPlayFlags,
lpszFlags);
Parameters
lpszDeviceID
Identifier of an MCI device. This identifier or alias is assigned when the
device is opened.
lpszPlayFlags
Flag for playing a device. The following table lists device types that
recognize the play command and the flags used by each type:
cdaudio
| from position
| to position
| digitalvideo
| from position
fullscreen
repeat
| reverse
to position
window
| sequencer
| from position
| to position
| | at time
from position
reverse
| scan
to position
| | fast
from position
reverse
scan
| slow
speed integer
to position
| waveaudio
| from position
| to position
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The following table lists the flags that can be specified in the lpszPlayFlags parameter and their meanings:
at time
| Indicates when the device should begin performing this command, or, if the
device has been cued, when the cued command begins. For more information, see the cue command.
| fast
| Indicates that the device should play faster than normal. To determine the
exact speed on a videodisc player, use the "speed" flag of the status command. To specify the speed more precisely, use the "speed" flag of this
command.
| from position
| Specifies a starting position for the playback. If the "from" flag is not
specified, playback begins at the current position. For cdaudio devices, if the "from" position is greater than the end position of the disc,
or if the "from" position is greater than the "to" position, the driver
returns an error. For videodisc devices, the default positions are in frames for CAV discs and in hours,
minutes, and seconds for CLV discs.
| fullscreen
| Specifies that a full-screen display should be used. Use this flag only when
playing compressed files. (Uncompressed files won't play full-screen.)
| repeat
| Specifies that playback should restart when the end of the content is reached.
| reverse
| Specifies that the play direction is backward. You cannot specify an ending
location with the "reverse" flag. For videodiscs, "scan" applies only to CAV
format.
| scan
| Plays as fast as possible without disabling video (although audio might be
disabled). For videodiscs, "scan" applies only to CAV format.
| slow
| Plays slowly. To determine the exact speed on a videodisc player, use the
"speed" flag of the status command. To specify the speed more precisely, use the "speed" flag of this
command. For videodiscs, "slow" applies only to CAV format.
| speed integer
| Plays a videodisc at the specified speed, in frames per second. This flag
applies only to CAV discs.
| to position
| Specifies an ending position for the playback. If the "to" flag is not
specified, playback stops at the end of the content. For cdaudio devices, if the "to" position is greater than the end position of the disc,
the driver returns an error. For videodisc devices, the default positions are in frames for CAV discs and in hours,
minutes, and seconds for CLV discs.
| window
| Specifies that playing should use the window associated with the device
instance. This is the default setting.
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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
Before issuing commands that use position values, you should set the desired
time format by using the set command. This command begins playing at the current speed, as set with the set "speed" command. The direction is reverse if the "reverse" flag is specified,
or if the "to" flag is specified as a value less than the "from" flag. If the
"from" flag is not specified, playback begins at the current position. The "to"
and "reverse" flags cannot be used together.
The following command plays the "mysound" device from position 1000 through
position 2000, sending a notification message when the playback completes:
play mysound from 1000 to 2000 notify
See Also
cue, set, status
Related Links
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Unix Manual Pages
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