Unisys Corp., striving to show its commitment to standards in the computer industry, announced technology agreements Wednesday with American Telephone & Telegraph Co. and Sun Microsystems Inc. Unisys said the agreements would bolster its use of Unix, a computer operating system or ``traffic cop'' that was developed by AT&T and is gaining popularity among commercial computer users. In addition to working with AT&T to enhance Unix, Unisys said it was licensing a computer chip design from Sun Microsystems, known as Sparc, that would be used in future Unisys computers running Unix. Unisys, the world's third-largest computer company, said its strong support for Unix set it apart from its two larger rivals, International Business Machines Corp. and Digital Equipment Corp. The company said its business based on Unix doubled last year and amounts to more than $500 million a year. ``There's no doubt by now that Unix is going to be a very sizable portion of the information systems industry,'' Jan Lindelow, Unisys senior vice president for corporate marketing and services, said in an interview.