Determining
and Changing the Current Position
When a file
or device is associated with an MCIWnd window, the playback position is
initially set at the start of the content, regardless of the media type. During
playback, the playback position moves linearly through the content and, if
playback is uninterrupted, eventually reaches the end of the content. If an
interruption occurs, the current playback position is the location at which
playback was stopped or paused.
You can
retrieve the locations for the beginning and end of the content by using the MCIWndGetStart and MCIWndGetEnd macros. You can determine
the length of the content by subtracting the value returned by MCIWndGetStart
from the value returned by MCIWndGetEnd, or by using the MCIWndGetLength macro. You can retrieve the
current playback position by using the MCIWndGetPosition macro, or you can retrieve
the playback position as a null-terminated string by using the MCIWndGetPositionString macro.
To change the
current playback position, use the MCIWndHomeF.C1KO, MCIWndEnd, and MCIWndSeek macros. You can move the
playback position to the start of the content by using MCIWndHome or to
the end of the content by using MCIWndEnd. Use MCIWndSeek to move
the playback position to any location in the content.
You can also
step through the content by using the MCIWndStep macro. Beginning from the
current playback position, this macro moves the playback position forward or
backward by a specified increment.
Note The units used
to specify position vary among the different media types and devices. For
example, the playback position for AVI files used by the MCIAVI device is
measured in frames; the playback position for CD audio, waveform-audio, and
MIDI files is measured in milliseconds.
Devices for
other media types and third-party devices might use other units. For
information about determining these units, see Playback Enhancements.