Function:     GDI_ERROR

Purpose:      Returns an error message associated with a gdi error code.

Category:     DISPLAY

File:         gdilib.c

Author:       K.G. Begeman

Use:          INTEGER GDI_ERROR( GDI_ERR,      Input     INTEGER
                                 ERR_STRING )  Output    CHARACTER*(*)

              GDI_ERROR      Returns 0 on success, -61 when error code
                             is not known.
              GDI_ERR        Error returned by gdi function (<0).
              ERR_STRING     String with error message.

Updates:      Feb 23, 1993: KGB Document created.