Highlights, UNIX System Services beneﬁts can include

cross-network management of data and applications, and the exploitation of traditional zSeries system strengths in an open environment.

Highlights

•X/Open UNIX 95 Branded

•Permanent z/OS UNIX Kernel (restart capability pro- vided in z/OS 1.3)

•Integrated/converged z/OS UNIX Sockets

•Web application and UNIX C program performance improvements

•Improved z/OS UNIX setup

•Multiprocess/Multiuser Kernel Support

•Performance enhancements include recompiled and optimized functions within the kernel, and shell and utili- ties; addition of Socket Functions; use of Communica- tion Storage Management buffer transfer instead of data movement; and optimized NFS Logical File System.

•Multiprocess/Multiuser can allow faster process creation for customers and reduced storage usage for servers

•Semaphores without contention using the hardware Per- form Locked Operation (PLO) instruction

•Shared memory (captured storage) can reduce real stor- age when sharing large amounts of virtual storage

•UNIX System Services and UNIX debugger add support for IEEE-ﬂ oating point

•UNIX System Services provides greater security granu- larity for HFS and zFS ﬁ le systems with support for Access Control Lists (ACLs)

•More ﬁ le descriptors per UNIX process are provided in z/OS 1.6, which supports up to 64K per process

•Additional support for 64-bit programming, conditional variables in shared memory, Euro symbol, and superkill support, along with enhancements to the automount daemon and Unicode

UNIX System Services beneﬁts can include:

•Development and execution of UNIX applications — z/OS is a UNIX platform

•Increased application portfolio on z/OS as Independent Software Vendors can use USS to port their applications to z/OS

•Portability of applications to and from other platforms

•Use of UNIX development skills in a z/OS environment

•Consolidate multiple UNIX systems

•Scalability for high growth UNIX applications

•Parallel Sysplex support to share UNIX ﬁ le systems ben- eﬁ ts with Web server applications and others who access the hierarchical ﬁ le system. This support can make your data and information that reside in the HFS available to your customers at any time, no matter where the applica- tions are running in the Parallel Sysplex environment.

Distributed Computing Services

z/OS Version 1 Release 6 base elements

Network File System (NFS)

DCE Base Services

Distributed File Service (including zFS and SMB)

z/OS UNIX supports hierarchical ﬁ le systems that use UNIX APIs. Applications can work with data in both UNIX hierarchical ﬁ le systems and traditional zSeries data sets.

zSeries File System (zFS)

zFile System (zFS) is the strategic UNIX ﬁ le system for z/OS and complements the z/OS Hierarchical File System (HFS). zFS uses the same APIs as HFS.

zFS can provide the following beneﬁts over HFS:

•Improved performance

•Additional function

–Disk space can be shared between ﬁ le systems in the same data set