Version number in an API call

The version of an API call determines the format of the parameter list. Although many of the parameter lists are the same for all versions, the formats documented here are specifically for version 6. For earlier formats, see the notes under the description of the VERSION parameter and the Parameter list subtopic for each call. Earlier formats may support a shorter version of the parameter list. The default API call version is VERSION=1.

The version in the buffer header determines the format of the data in the buffer. The default buffer version is VERSION=1. For new programs, we recommend that VERSION=7 be used.

There is no requirement that the buffer version match the program object version. However, you may lose data if the target program has content not supported by the data buffer format you are using.

Version 2 (and higher) data buffers support all possible contents of a PO2 format program object.
Version 4 (and higher) data buffers support all possible contents of a PO3 format program object.
Version 6 (and higher) data buffers support all currently defined contents (as of z/OS® 1.3) of a PO4 format program object.
Version 7 (and higher) data buffers support all currently defined contents (as of z/OS 1.10) of a PO5 format program object.