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#define INCL_VIO
 
USHORT VioScrollLf(usTopRow, usLeftCol, usBotRow, usRightCol, cbColumns,
    pbCell, hvio)
USHORT usTopRow;      /* top row                                */
USHORT usLeftCol;     /* left column                            */
USHORT usBotRow;      /* bottom row                             */
USHORT usRightCol;    /* right column                           */
USHORT cbColumns;     /* number of blank columns                */
PBYTE pbCell;         /* pointer to the cell to write           */
HVIO hvio;            /* video handle                           */
 
The VioScrollLf function scrolls the current screen toward the left.
 
The VioScrollLf function is a family API function.
 
Parameter   Description
────────────────────────────────────────────────────────────────────────────
 
usTopRow    Specifies the top row of the screen area to scroll.
 
usLeftCol   Specifies the leftmost column of the screen area to scroll.
 
usBotRow    Specifies the bottom row of the screen area to scroll.
 
usRightCol  Specifies the rightmost column of the screen area to scroll.
 
cbColumns   Specifies the number of columns of spaces to be inserted at the
            right. If this parameter is zero, no columns are inserted.
 
pbCell      Points to a character/attribute combination, called a cell, that
            fills the screen area left blank by the scrolling.
 
hvio        Identifies an advanced video-input-and-output (AVIO)
            presentation space. For AVIO programs, this handle must have
            been created previously 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_COL
     ERROR_VIO_INVALID_HANDLE
     ERROR_VIO_ROW
 
Comments
 
If the usTopRow and usLeftCol parameters are zero, they identify the
upper-left corner of the screen. If you specify a value greater than the
maximum for usTopRow, usLeftCol, usBotRow, usRightCol, or cbColumns, the
maximum value for that parameter is used. Maximum values depend upon the
dimensions of the screen being used.
 
You can use the VioScrollLf function to clear the screen by setting
usTopRow and usLeftCol to zero and usBotRow, usRightCol, and cbColumns to
their maximum values. The function clears the screen by using the
character/attribute combination pointed to by the pbCell parameter.
 
Example
 
This example calls VioScrollLf to fill the last ten columns at the right of
the screen with red hearts on a black background (a value of 0xFFFF is used
for usBotRow and usRightCol).
 
BYTE bCell[2];
bCell[0] = 0x03;     /* heart character     */
bCell[1] = 0x04;     /* red attribute (EGA) */
VioScrollLf(0,       /* top row             */
    0,               /* left column         */
    0xFFFF,          /* bottom row          */
    0xFFFF,          /* right column        */
    10,              /* columns             */
    bCell,           /* cell to write       */
    0);              /* video handle        */
 
See Also
 
VioCreatePS, VioScrollDn, VioScrollRt, VioScrollUp
 
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