Execute Channel Program: Difference between revisions

Revision as of 15:21, 3 March 2018

Revision as of 23:05, 21 April 2018

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==Exits (Appendages)==

A comprehensive list of "[[User exit|exits]]" (called, in the EXCP context, "appendages") allows authorized programs to override or augment many of the system security and data integrity checks. Most of these exits (really, closed subroutines) are supported for compatibility with earlier instances of the OS, but the functions of several have been modified or extended for MVS. The exits are specified in the DCB as the last two characters of the module name IGG019xx. where xx = WA to Z9 inclusive. These module names are reserved for userinstallation-written appendages. Any other name of the form IGG019xx is reserved for use by IBM access methods.<ref>IGG = I/O Support component prefix; 019 = Open SVC sub-component; xx = sub-function</ref> Appendages must reside in SYS1.SVCLIB (SYS1.LPALIB in SVS or later instances of the OS).

==Dataset integrity==