Enterprise Linux Today: SAS Institute Brings S/390 Cross Compilers to LinuxMar 06, 2001, 14:50 (9 Talkback[s])
(Other stories by Scott Courtney)
"The SAS Institute has announced the availability, in the first quarter of 2001, of Version 7.0 of their SAS/C and SAS/C++ cross-platform compilers for Linux development hosts. These tools allow IBM mainframe applications, targeted for OS/390 or VM/ESA, to be created and compiled on non- mainframe development hosts. Previous versions of SAS/C and SAS/C++ have supported AIX, Solaris, NT, and HP-UX as development platforms. Version 7.0 drops HP-UX but adds support for Intel Linux. (HP-UX is still supported for previous versions.) Gary T. Ciampa, Product Manager for the compiler team at SAS Institute, says that other Linux ports may be in the works, depending on customer demand. The company is seriously considering a port to Linux on S/390. Says Ciampa, "We anticipate Linux/390 as a natural migration path for our development community."
"According to Ciampa, cross compilation is often better for S/390 C/C++ development than a native environment because it "allows developers who may not be that familiar with the mainframe environment to develop and build applications in the familiar Linux framework that are targeted for the S/390 environment." In fact, the compilers can easily be integrated into the standard Linux framework using tools like lexx, yacc, and make. Ciampa says that many of SAS Institute's Linux customers are companies that are scaling up UNIX and Linux applications to the mainframe, and that developers don't want to have to learn a new tool set."
"During the build process, the early stages of compilation and linking are performed entirely on the development host. Only when it is time to link against mainframe load modules, or to mark the final binary as being executable, must the process move to the mainframe hardware. This, says Ciampa, can save time and money for the developer. "Compilation speed is almost instantaneous, whereas in the mainframe environment you're traditionally batch oriented. We've seen some customers go from ten hours to under thirty minutes to rebuild an entire [large] application." For the late stages, remote execution protocols such as rexec and FTP can eliminate the need to logon to the mainframe at all. Mainframes running IBM's OS/390 operating system support a special FTP command set that sends the uploaded data stream into the system's batch queue instead of to a regular data file, using the Job Entry Subsystem (JES) facility that has existed since the days of Hollerith cards. It's a proven, reliable, and secure way to trigger jobs remotely, because it can be set up so that the actual code isn't uploaded, but rather a simple trigger that causes a pre-defined job to be started."