oping: Improve parsing of the "-z" argument.
oping: Improve parsing of the "-z" argument.

octo/liboping,iseki-masaya/liboping,barak/liboping,barak/liboping,iseki-masaya/liboping,octo/liboping,barak/liboping,octo/liboping,iseki-masaya/liboping,iseki-masaya/liboping,octo/liboping