I've included the openpty module in a project, and I see that it doesn't work on all platforms. I assumed that I should test HAVE_OPENPTY to see if I got it, but HAVE_OPENPTY is undefined in my config.h, even though it's set to 1 in config.log. Further, I don't see how HAVE_OPENPTY can be 0, since my glibc/Linux system definitely has openpty.