There's a note in the POSIX rationale that mandating CHAR_BIT be 8 was a concession made that was necessary to maintain alignment with C99 without throwing out sockets/networking, but I've never seen the explanation of what exactly the conflict was. Does anyone have anecdotes or citations for why it was deemed necessary?
Edit: I've gotten a lot of speculative answers regarding why it's desirable for CHAR_BIT to be 8, and I agree, but what I'm really looking for is what the technical conflict between C99 and the networking stuff in POSIX is. My best guess is that it has something to do with C99 requiring uint*_t to be exact-sized types (no padding) whereas the inttypes.h previously in POSIX made no such requirement.