People keep removing UNIX code

• the access(), tell(), alarm(), pause() and setpgrp() system calls (these seem to have been removed from V6; as the entries in sysent.c are there, but blank)
• System V has the snake game, but for some reason has removed the termcap support, making it work on only a few terminal types.

But let's face it, the code was never removed. The authors of the documents don't know which direction time flows in. Here's a clue to the first one about v6. If you look in v7 you see:

sysent.c:       0, 0, nullsys,                  /* 39 = setpgrp (not in yet) */

Oops, it wasn't removed--it had not been added yet. Similarly nobody removed termcap from SysV games, it hadn't been added yet either.