To enable test coverage for a PL/I program or module use the -testcover option when compiling with mfplx or mfpli.
mfplx -debug -testcover myprog.pli
or
mfpli -debug -testcover prog1.pli mfpli prog2.pli ldpli prog1.o prog2.o
Test coverage is only supported for code compiled for debug. If the -testcover option is used, the code will be compiled for debug even if -debug is not specified. Note that by using mfpli and ldpli to compile and link you can freely mix modules compiled with and without test coverage.