subcalls.hlp (Topic list)
VioShowBuf (1.2)
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#define INCL_VIO
 
USHORT VioShowBuf(offLVB, cbOutput, hvio)
USHORT offLVB;      /* offset into logical video buffer */
USHORT cbOutput;    /* length                           */
HVIO hvio;          /* video handle                     */
 
The VioShowBuf function updates the physical screen from the logical video
buffer (LVB). You may use the logical video buffer to directly manipulate
information displayed on the screen.
 
The VioShowBuf function is a family API function.
 
Parameter  Description
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offLVB     Specifies the offset into the logical video buffer at which the
           screen update is to start.
 
cbOutput   Specifies the length (in bytes) of the screen area to update.
 
hvio       Identifies an advanced video-input-and-output (AVIO) presentation
           space. For AVIO programs, this handle must have been created
           using the VioCreatePS function. For other programs, hvio must be
           NULL.
 
Return Value
 
The return value is zero if the function is successful. Otherwise, it is an
error value, which may be one of the following:
 
     ERROR_VIO_INVALID_HANDLE
     ERROR_VIO_DETACHED
 
Comments
 
If a background process calls VioShowBuf, the function will return
ERROR_VIO_DETACHED.
 
Example
 
This example retrieves the address of the logical video buffer, makes
changes to that buffer, and calls VioShowBuf to update the physical video
buffer from the logical video buffer.
 
PBYTE pbLVB;
USHORT cbOutput;
VioGetBuf((PULONG) &pbLVB, &cbOutput, 0);
    .
    .
    .
VioShowBuf(0,         /* offset into logical video buffer */
    cbOutput,         /* length of screen area            */
    0);               /* video handle                     */
 
See Also
 
VioCreatePS, VioGetBuf, VioGetPhysBuf