#CHKSUB

#ChkSub

Syntax

#ChkSub {subsystem#} {version#}

What It Does

If a #ChkSub directive is encountered, the compiler verifies that the version# is the same as the compiler's own version for the specified subsystem. If not, an error is generated, but compilation can be continued.

Not everything can be automatically checked by the compatibility system. For example, the compiler might find old package source due to an incorrect DFPATH. If you compile outdated code with a new compiler, it will run with a new runtime even if the code itself is obsolete. To help guard against this, there is a compiler directive you can use called #ChkSub.