UNIX System Services

UNIX System Services (USS) is a required, included component of z/OS. USS is a certified UNIX operating system implementation (XPG4 UNIX® 95) optimized for mainframe architecture. It is the first UNIX 95 to not be derived from the AT&T source code. Through integration with the rest of z/OS, additional Time Sharing Option (TSO) commands are available alongside the usual UNIX services, making it possible to process UNIX files using ISPF. Extensions in JCL make it possible to use these files in batch processing.