UNIX System Services

UNIX System Services
DeveloperIBM
OS familyUNIX - POSIX
Working stateCurrent
Source modelClosed source
Initial release1998; 26 years ago (1998)[1] (Name changed from OpenEdition to OS/390 UNIX System Services)
Latest releaseVersion 3.1 (V3R1) / September 29, 2023; 13 months ago (2023-09-29)
Marketing targetEnterprise / Mainframes
Available inEnglish and most other languages
Platformsz/Architecture
LicenseProprietary
Official websitez/OS UNIX System Services
History of IBM mainframe operating systems
Early mainframe computer OSes
Miscellaneous S/360 line OSes
DOS/360 and successors (1966)
OS/360 and successors (1966)
VM line
TPF line
UNIX and Unix-like

z/OS UNIX System Services (z/OS UNIX, or informally USS) is a base element of z/OS.[2] z/OS UNIX 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.

  1. ^ "UNIX System Services z/OS Version 1 Release 7 Implementation" (PDF). Software Support Manual. IBM. March 2006. SG24-7035. Name changed from OpenEdition to OS/390 UNIX System Services
  2. ^ "z/OS base elements". ibm.com.