Purpose of this information: This information presents the information you need to plan for and run an IBM® z/OS® system with support for z/OS UNIX System Services (z/OS UNIX). This element and the Language Environment® element and z/OS XL C/C++ compiler provide an application programming interface (API) and a shell interface based on the open systems standards of the Institute of Electrical and Electronics Engineers (IEEE) Portable Operating System Interface (POSIX) project, the Federal Information Processing Standard (FIPS), and the X/Open Portability Guide Issue 4 (XPG4).

The z/OS Network File System and the z/OS Distributed File Service provide additional capability.

This information supports z/OS (5650-ZOS). It assumes that the readers are familiar with z/OS systems and its accompanying products. It also assumes that you are using Security Server for z/OS. RACF® is a component of the Security Server for z/OS. Instead of RACF, you could use an equivalent security product if it supports the system authorization facility (SAF) interfaces required by z/OS UNIX, which are documented in .

Who should read this information? This information is for the system programmers, storage administrators, security administrators, and security auditors who run a z/OS system with z/OS UNIX. On other open systems, some system programmer tasks might be done by an administrator.