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info command

The info command retrieves a hardware description from a device. All MCI devices recognize this command.

To send this command, call the mciSendString function with the lpszCommand parameter set as follows.

_stprintf_s(
  lpszCommand, 
  TEXT("info %s %s %s"), 
  lpszDeviceID, 
  lpszInfoType, 
  lpszFlags
); 

Parameters

lpszDeviceID

Identifier of an MCI device. This identifier or alias is assigned when the device is opened.

lpszInfoType

Flag that identifies the type of information required. The following table lists device types that recognize the info command and the flags used by each type.

Value Meaning Meaning
cdaudio info identityinfo upc product
digitalvideo audio algorithmaudio qualityfileproductstill algorithmstill quality usageversionvideo algorithmvideo qualitywindow text
overlay fileproduct window text
sequencer copyrightfile nameproduct
vcr product version
videodisk product
waveaudio fileinput outputproduct

The following table lists the flags that can be specified in the lpszInfoType parameter and their meanings.

Value Meaning
audio algorithm Returns the name of the current audio compression algorithm.
audio quality Returns the name for the current audio quality descriptor. This might return "unknown" if the application has set parameters to specific values that do not correspond to defined qualities.
copyright Retrieves the MIDI file copyright notice from the copyright meta event.
file Retrieves the name of the file used by the compound device. If the device is opened without a file and the load command has not been used, a null string is returned.
info identity Produces a unique identifier for the audio CD currently loaded in the player being queried.
info 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.
input Retrieves the description of the current input device. Returns "none" if an input device is not set.
name Retrieves the sequence name from the sequence/track name meta event.
output Retrieves the description of the current output device. Returns "none" if an output device is not set.
product Retrieves a description of the device. This information often includes the product name and model. The string length will be 31 characters or fewer.
still algorithm Returns the name of the current still image compression algorithm.
still quality Returns the name for the current still image quality descriptor. This might return "unknown" if the application has set parameters to specific values that do not correspond to defined qualities.
usage Returns a string describing usage restrictions that might be imposed by the owner of the visual or audio data in the workspace.
version Returns the release level of the device driver and hardware.
video algorithm Returns the name of the current video compression algorithm.
video quality Returns the name for the current video quality descriptor. This might return "unknown" if the application has set parameters to specific values that do not correspond to defined qualities.
window text Retrieves the caption of the window used by the device.

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 Value

Returns zero if successful or an error otherwise.

Examples

The following command retrieves a description of the hardware associated with the "mysound" device.

info mysound product

Requirements

Requirement Value
Minimum supported client
Windows 2000 Professional [desktop apps only]
Minimum supported server
Windows 2000 Server [desktop apps only]

See also

MCI

MCI Command Strings

load