History/Common JCL
Many of these utilities were designed by IBM users, through the group SHARE, and then modified or extended by IBM from versions originally written by a user.
These utilities are usually invoked via Job Control Language (JCL). They tend to use common JCL DD identifiers for their data sets:
- SYSIN — input file for the 'commands' for the utility. Often set to DUMMY if the default action is desired.
- SYSUT1 — input file.
- SYSUT2 — output file.
- SYSUT3 — work (spill) file for input (SYSUT1) (often not used).
- SYSUT4 — work (spill) file for output (SYSUT2) (often not used).
- SYSPRINT — output file for printed output from the utility.
- SYSOUT — output file for messages from the utility.
- SYSUDUMP — output file for a system 'dump' if the program fails.
Read more about this topic: IBM Mainframe Utility Programs
Famous quotes containing the words history and/or common:
“One classic American landscape haunts all of American literature. It is a picture of Eden, perceived at the instant of history when corruption has just begun to set in. The serpent has shown his scaly head in the undergrowth. The apple gleams on the tree. The old drama of the Fall is ready to start all over again.”
—Jonathan Raban (b. 1942)
“Uniform ideas originating among entire peoples unknown to each other must have a common ground of truth.”
—Giambattista Vico (1688–1744)