Introduction : Development and Execution Environments
The SAS/C Compiler
supports a number of development and execution environments that facilitate
the efficient development of applications designed to run on the IBM System/370
mainframe. The SAS/C C++ Development
System is an add-on product that extends the capabilities of these development
environments to support the C++ programming language. The following paragraphs
briefly describe these development environments.
Traditionally,
SAS/C applications
have been developed in one of the System/370 operating environments: TSO,
CMS, or OS/390 batch. This book is designed to provide information you will
need to use the SAS/C Compiler effectively
in the mainframe SAS/C development
environment.
There are two versions of the SAS/C Compiler
available under CMS: the 370 mode version and the XA version. The 370 mode
version of the compiler (and programs developed with it) runs under CMS for
VM/SP Releases 3, 4, 5, 6, and later. This version runs in tolerance mode
(XA-mode but only AMODE 24) under CMS for VM/XA SP Releases 1, 2, and later.
The XA version works under the CMS associated with releases of VM after Release
5 of VM/SP. Under VM extended architecture systems, programs run in exploitation
mode, that is, they run AMODE 31, taking advantage of storage above the 16-megabyte
line.
The
SAS/C CICS
Command Language Translator extends the mainframe execution environment so
that you can write C programs that interact with the IBM Customer Information
Control System (CICS). The SAS/C Library
supports the CICS run-time environment under TSO, CMS, and OS/390 batch. The SAS/C CICS
Command Language Translator is documented in the
SAS/C CICS User's Guide.
With the UNIX System
Services (USS) subsystem from IBM, the SAS/C Library
supports the operating system interface defined by the ISO POSIX 1003.1 standard.
This support extends the mainframe development environment to the USS shell
under OS/390. This support is described in Developing Applications for Use with UNIX System Services OS/390.
The SAS/C Cross-Platform
Compiler and the SAS/C C++ Cross-Platform
Development System are the cornerstones of a cross-platform development environment
that enables you to compile mainframe SAS/C and SAS/C C++
applications on a UNIX workstation. These add-on products run on the workstation
and produce prelinked output files that can be transferred to an IBM System/370
mainframe, where they can be linked to produce an executable load module.
There are several benefits to using SAS/C and
C++ cross-platform software.
-
Reduced mainframe load
-
By moving compilations off the mainframe,
mainframe CPU cycles are preserved for other users. This can amount to a significant
reduction in mainframe requirements, directly translating into a cost savings.
-
Improved source management
-
Developers may take advantage of improved
source management tools, as well as the UNIX hierarchical file system.
-
Improved build management
-
Developers may take advantage of improved
build management tools, such as
make
.
-
Improved compilation turnaround
-
In a heavy development environment, developers
often find that performing compilations locally can result in a better turnaround
time.
For more information about the cross-platform development
environment, refer to
SAS/C Cross-Platform Compiler and C++ Development System User's Guide.
The following points should be considered when determining compatibility
between the two CMS versions of the compiler:
Copyright © 2001
by SAS Institute Inc., Cary, NC, USA. All rights reserved.
