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
|
reverse |
|
sequencer |
from position
|
to position |
|
vcr |
at time |
scan |
|
videodisc |
fast |
slow |
|
waveaudio |
from position
|
to position |
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. |
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