Probably a bit off-topic here, but I'm curious with OpenBSD's version of the Unix utility 'patch'. My module File::Patch::Undoable is trying to test whether patch supports --dry-run option. OpenBSD's patch does not, but unlike other flavors which also do not support --dry-run (like FreeBSD's), it does not return non-zero exit code when fed unknown option, causing CPANTesters to report lots of errors for my dist (solely on OpenBSD, of course).

Can someone with access to an OpenBSD system help give some idea on identifying this particular flavor? Otherwise, I might as well check for $^O specifically.