SaveScreenBitmap

WORD SaveScreenBitmap(LPRECT lpRect, WORD wCommand);

Saves a single bitmap from the display or restores a single, previously-stored bitmap to the display. The function is used, for example, when a menu is pulled down, to store the part of the screen that is "behind" the menu until the menu is closed.

Returns 1 if successful. It is zero for any of the following error conditions:
"Shadow memory" does not exist (save, restore, ignore).

"Shadow memory" is already in use (save).

"Shadow memory" is not in use (restore).

"Shadow memory" has been stolen or trashed (restore).

lpRect

Address of a RECT structure that contains the rectangle to use.

wCommand

Action to take. Can be one of these values:

0	Saves the rectangle.
1	Restores the rectangle.
2	Discards the previously saved rectangle, if there was one.

The export ordinal for this function is 92.

Because SaveScreenBitmap can save only one bitmap at a time, the device driver must maintain a record of whether or not the save area is currently in use.

The bitmap is stored in "shadow memory" (that is, memory that the device allocates and controls). Therefore, the device can save the bitmap in whatever form is most convenient.