Function:     GDI_GRCLEAR

Purpose:      Clears graphics planes.

Category:     DISPLAY

File:         gdilib.c

Author:       K.G. Begeman

Use:          INTEGER GDI_GRCLEAR( GDI_ID ,     Input      INTEGER
                                   PMASK )      Input      INTEGER

              GDI_GRCLEAR    Returns zero on succes, negative on error.
              GDI_ID         Display id as returned by GDI_OPEN.
              PMASK          Mask which specifies which planes should be
                             cleared.

Updates:      Jan  3, 1991: KGB Document created.