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MMIOM_READ

The MMIOM_READ message is sent to an I/O procedure by the mmioRead function to request that a specified number of bytes be read from an open file.

MMIOM_READ 
lParam1 = (LPARAM) lBuffer 
lParam2 = (LPARAM) cbRead 

Parameters

lBuffer

Pointer to the buffer to be filled with data read from the file.

cbRead

Number of bytes to read from file.

Return Values

Returns the number of bytes actually read from the file. If no more bytes can be read, the return value is 0. If there is an error, the return value is - 1.

Remarks

The I/O procedure is responsible for updating the lDiskOffset member of the MMIOINFO structure to reflect the new file position after the read operation.

Requirements

**  Windows NT/2000/XP:** Included in Windows NT 3.1 and later.
**  Windows 95/98/Me:** Included in Windows 95 and later.
**  Header:** Declared in Mmsystem.h; include Windows.h.

See Also

mmioRead, MMIOINFO