What is an object deck?

An object deck is a collection of one or more compilation units produced by an assembler, compiler, or other language translator, and used as input to the binder (or linkage editor).

An object deck is in relocatable format with machine code that is not executable. A load module is also relocatable, but with executable machine code. A load module is in a format that can be loaded into virtual storage and relocated by program manager, a program that prepares load modules for execution by loading them at specific storage locations.

Object decks and load modules share the same logical structure consisting of:

Control dictionaries, containing information to resolve symbolic cross-references between control sections of different modules, and to relocate address constants
Text, containing the instructions and data of the program
An end-of-module indication, which is an END statement in an object deck, or an end-of-module indicator in a load module.

Object decks are stored in a partitioned data set identified by the SYSLIN or SYSPUNCH DD statement, which is input to the next linkage edition process.