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:
“When the coherence of the parts of a stone, or even that composition of parts which renders it extended; when these familiar objects, I say, are so inexplicable, and contain circumstances so repugnant and contradictory; with what assurance can we decide concerning the origin of worlds, or trace their history from eternity to eternity?”
—David Hume (1711–1776)
“We have too many intellectuals who are afraid to use the, the pistol of common sense.”
—Samuel Fuller (b. 1911)