System library

Unless a job or step specifies a private library, the system searches for a program in the system libraries when you code:

   //stepname  EXEC  PGM=program-name

The system looks in the libraries for a member with a name or alias that is the same as the specified program-name. The most used system library is SYS1.LINKLIB, which contains executable programs that have been processed by the linkage editor.

If an earlier DD statement in the job defines the program as a member of a system library, refer to that DD statement to execute the program:

   //stepname  EXEC  PGM=*.stepname.ddname