(19)

(11)

EP 0 321 555 A1

(12)

(43) Date of publication: 28.06.1989 Bulletin 1989/26 (21) Application number: 88906462.0 (22) Date of filing: 27.06.1988

(51) International Patent Classification (IPC):  G06F 12/ 08( . ) G06F 3/ 06( . ) (86) International application number: PCT/US1988/002146 (87) International publication number: WO 1989/000313 (12.01.1989 Gazette 1989/02)

(84) Designated Contracting States: AT BE CH DE FR GB IT LI LU NL SE (30) Priority: 01.07.1987 US 19870068386 (71) Applicant: UNISYS CORPORATION Blue Bell, PA 19424-0001 (US)	(72) Inventors: TORTORELLI, Daniel, W. San Leandro, CA 94579 (US) WARNER, Nicholas, M. Livermore, CA 94550 (US) GLIDER, Joseph Mt. View, CA 94043 (US) (74) Representative: Eisenführ, Speiser & Partner  Martinistrasse 24 D-28195 Bremen D-28195 Bremen (DE)