This function returns the desktop structure, which contains the information about the current state of the desktop background.

#define INCL_WINWINDOWMGR /* Or use INCL_WIN, INCL_PM, */
#include <os2.h>

HWND        hwndDesktop;  /*  Desktop-window handle. */
PDESKTOP    pdsk;         /*  Desktop-state structure. */
BOOL        rc;           /*  Success indicator. */

rc = WinQueryDesktopBkgnd(hwndDesktop, pdsk);