From Wikipedia, the free encyclopedia
I'm not sure this is useful info.
(==System generation procedures==)
There is no "standard" procedure for sysgens on systems from different vendors. Sysgen procedures fall into at least three categories:
- Compile or assemble operating system kernel, nucleus, or supervisor. In this case other sysgen tasks such as building system libraries are usually manually performed. Systems using this procedure include:
- Burroughs large systems Master Control Program (MCP). The Burroughs MCPs were written in a high-level ALGOL-like languages ESPOL or NEWP. The MCP is tailored by coding $OMIT conditional-compilation pragmas, which conditionally bypass compilation of specified pieces of code.
- IBM System/360 Disk Operating System (DOS) was written in assembler. The systems programmer performing the sysgen codes macros specifying the desired options and assembles the supervisor.
- Linux still provides this as an option, called tailoring the kernel. The Linux kernel is coded in C and it is possible to make source changes and rebuild the kernel.
- Some procedures accept a set of specifications and perform all the tasks necessary to build a tailored system.
- IBM OS/360 had a two-step procedure called Stage I and Stage II. In Stage I the programmer specified the options for the system in a set of macros and assembled them. The output of Stage I was a job stream which contained the job control to perform all the necessary assemblies, link edits, and to create the required system libraries and copy the necessary modules into them.
- Well, that might help explain it to newer readers familiar with configuring Linux kernels, and also helps keep it from being seen as IBM mainframe OS-specific. (As I remember, RSX-11 had a similar configuration mechanism, conditionally assembling parts of the supervisor.) Guy Harris (talk) 22:56, 23 June 2013 (UTC)