MCI_INFO command
The MCI_INFO command retrieves string information from a device. All devices recognize this command. Information is returned in the lpstrReturn member of the structure identified by lpInfo. The dwRetSize member specifies the buffer length for the returned data.
To send this command, call the mciSendCommand function with the following parameters.
MCIERROR mciSendCommand(
MCIDEVICEID wDeviceID,
MCI_INFO,
DWORD dwFlags,
(DWORD) (LPMCI_INFO_PARMS) lpInfo
);
Parameters
-
wDeviceID
-
Device identifier of the MCI device that is to receive the command message.
-
dwFlags
-
MCI_NOTIFY, MCI_WAIT, or, for digital-video and VCR devices, MCI_TEST. For information about these flags, see The Wait, Notify, and Test Flags.
-
lpInfo
-
Pointer to an MCI_INFO_PARMS structure. (Devices with extended command sets might replace this structure with a device-specific structure.)
Return Value
Returns zero if successful or an error otherwise.
Remarks
The following additional standard and command-specific flag applies to all devices supporting MCI_INFO:
-
MCI_INFO_PRODUCT
-
Obtains a description of the hardware associated with a device. Devices should supply a description that identifies both the driver and the hardware used.
The following additional flags apply to the cdaudio device type:
-
MCI_INFO_MEDIA_IDENTITY
-
Produces a unique identifier for the audio CD currently loaded in the player being queried. This flag returns a string of 16 hexadecimal digits.
-
MCI_INFO_MEDIA_UPC
-
Produces the Universal Product Code (UPC) that is encoded on an audio CD. The UPC is a string of digits. It might not be available for all CDs.
The following additional flags apply to the digitalvideo device type:
-
MCI_DGV_INFO_ITEM
-
A constant indicating the information desired is included in the dwItem member of the structure identified by lpInfo. The following constants are defined for digital-video devices:
-
MCI_DGV_INFO_AUDIO_ALG
-
Returns the name for the current audio compression algorithm.
-
MCI_DGV_INFO_AUDIO_QUALITY
-
Returns the name for the current audio quality descriptor.
-
MCI_DGV_INFO_STILL_ALG
-
Returns the name for the current still image compression algorithm.
-
MCI_DGV_INFO_STILL_QUALITY
-
Returns the name for the current still image quality descriptor.
-
MCI_DGV_INFO_USAGE
-
Returns a string describing usage restrictions that might be imposed by the owner of the visual or audible data in the workspace.
-
MCI_DGV_INFO_VIDEO_ALG
-
Returns the name for the current video compression algorithm.
-
MCI_DGV_INFO_VIDEO_QUALITY
-
Returns the name for the current video quality descriptor.
-
MCI_INFO_VERSION
-
Returns the release level of the device driver and hardware. Device driver developers must document the syntax of the returned string.
-
MCI_DGV_INFO_TEXT
-
Obtains the window caption.
-
MCI_INFO_FILE
-
Obtains the path and filename of the last file specified with the MCI_OPEN or MCI_LOAD command. If a file has not been specified, the device returns a null-terminated string. This flag is supported only by devices that return TRUE to the MCI_GETDEVCAPS_USES_FILES flag of the MCI_GETDEVCAPS command.
For digital-video devices, lpInfo points to an MCI_DGV_INFO_PARMS structure.
The following additional flags apply to the sequencer device type:
-
MCI_INFO_COPYRIGHT
-
Obtains the MIDI file copyright notice from the copyright meta event.
-
MCI_INFO_FILE
-
Obtains the filename of the current file. This flag is supported only by devices that return TRUE when you call the MCI_GETDEVCAPS command with the MCI_GETDEVCAPS_USES_FILES flag.
-
MCI_INFO_NAME
-
Obtains the sequence name from the sequence/track name meta event.
The following additional flag applies to the vcr device type:
-
MCI_VCR_INFO_VERSION
-
Sets lpstrReturn member of the MCI_INFO_PARMS structure to point to the version number. Also sets the dwRetSize member equal to the length of the string pointed to.
The following additional flags apply to the overlay device type:
-
MCI_INFO_FILE
-
Obtains the filename of the current file. This flag is supported only by devices that return TRUE to the MCI_GETDEVCAPS_USES_FILES flag of the MCI_GETDEVCAPS command.
-
MCI_OVLY_INFO_TEXT
-
Obtains the caption of the window associated with the video-overlay device.
The following additional flags apply to the waveaudio device type:
-
MCI_INFO_FILE
-
Obtains the filename of the current file. This flag is supported by devices that return TRUE when you call the MCI_GETDEVCAPS command with the MCI_GETDEVCAPS_USES_FILES flag.
-
MCI_WAVE_INPUT
-
Obtains the product name of the current input.
-
MCI_WAVE_OUTPUT
-
Obtains the product name of the current output and its value is device specific.
Requirements
Requirement | Value |
---|---|
Minimum supported client |
Windows 2000 Professional [desktop apps only] |
Minimum supported server |
Windows 2000 Server [desktop apps only] |
Header |
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