Autzoo.1481 net.bugs.v7 utcsrgv!utzoo!henry Thu Mar 11 17:29:19 1982 (unsigned)char Casting a char value to unsigned in the V7 compiler does a very nice job of something that is awkward to get otherwise: zero-extending rather than sign-extending a char. The trouble is, that's a bug: be warned. The official behavior of casts, according to DMR, is that they act like assignment to a temporary variable of that type. Which means that casting char to unsigned goes via int the same way a normal assignment does, and the sign gets extended. This is fixed in DMR's more recent C compilers (when I asked him, he wasn't sure whether the 3.0 compiler was recent enough).