builds/zos includes:
README.md: Overview of z/OS UNIX System Services port (Markdown)
makelibzmq: Compile src/*.cpp and make libzmq.a
maketests: Compile tests/*.cpp and make test_* executables
runtests: Run tests/test_* executables and report results
makeclean: Remove built files
zc++: /bin/c++ wrapper supplying required build arguments
cxxall: run zc++ for all *.cpp files in directory
platform.hpp: pre-generated (and edited) src/platform.hpp for z/OS
test_fork.cpp: updated tests/test_fork.cpp that completes on z/OS