Loading and deleting programs in different environments

This topic describes load module name support, the search order for the loading and deleting of library subroutines, and the interface to load and delete services. This process can vary, depending on the environment (MVS™, CICS® or z/OS UNIX System Services).

Under MVS, the search order can be specified on the interface to the CEEPLOD2 service. This service allows the CWI writer to specify the search order in the following:

Search data sets only
Search the UNIX file system only
First search data sets, if not found then search the UNIX file system
First search the UNIX file system, if not found then search data sets

The name specified on a load request can affect the search order. The following rules apply to the name and search order:

If the single slash ('/') character is anywhere in the name and is not covered by the rules below, then search the UNIX file system only.
If the characters ('./') are the first 2 characters in the name, then search the UNIX file system only.
If the characters ('//') are the first 2 characters, then search data sets only. The first 2 characters are then deleted from the name that is passed to the operating system.

When searching data sets, the name is always folded to uppercase. When going to the UNIX file system, the name is passed "as is".

When an MVS module search is performed, the load macro is issued and the usual program search order prevails. When searching for the executable module in the UNIX file system, then the BPX1LOD service is used.

In a CICS environment, Language Environment uses the EXEC CICS load services.

Finally, in a z/OS UNIX System Services environment, under CICS, loading from the hierarchical file system is not supported.