In paper-tape days, nul or null was all zeros - or on the actual physical tape, all holes. (One might think that each hole was an "on" bit or binary 1 but not so.) The concept was, I think, that you could correct a tape by repunching the bad character so that spot was all holes. I think this was for both five-bit and eight-bit tapes. Just a bit of trivia.
> ----- Original Message ----- > From: Duncan > Sent: 10/01/12 07:56 PM > To: pan-users@nongnu.org > Subject: Re: [Pan-users] article-cache v 0.139 > > Rhialto posted on Mon, 01 Oct 2012 18:34:51 +0200 as excerpted: > > > On Mon 01 Oct 2012 at 11:43:08 +0000, Duncan wrote: > >> But usenetbucket's devs apparently didn't read past "null", and took it > >> to be "null-as-in-byte-0x00". > > > >> I've often wondered just how often that ambiguity causes issues. Here > >> we have a case in point! > > > > Another issue that seems to confuse many people is that the character > > with value 0 is called NUL, with one L, and not NULL, or null, or > > anything else with 2 ls. All control characters 0-31 have 3 character > > uppercase names. So if the RFC says "null", that also means it can't be > > "NUL". > > I've seen that point made before, but I've never checked it, and don't > remember seeing it in the intro programming (pascal) classes I did have. > > Without that research it does ring a bit hollow, tho. As in, all the > other three-letter control-characters in ASCII, many of which made a > great deal of sense back in the telegraph-style physical printer control > output days, but not so much now. With certain exceptions (line-end > chars, which can actually differ, tabs, nul(l), in some contexts ctrl-C, > not so many others), they're generally simply data-stream characters now, > like any other, or at least like any other out of the normal printing > range. > > So here, I always thought NUL was much like SOH, ETX, EOT, ACK, BEL, > NAK... > > In fact, take a look at this ASCII table, which lists those same as > (null), (start of heading), (end of text), (end of transmission), > (acknowledge), (bell), (negative acknowledge)... > > http://www.asciitable.com/ > > IOW, at least according to /that/ table, NUL is INDEED a standard 3- > letter short form for "null", just as SOH is the standard 3-letter short > form of "start of heading". > > But of course not everything found on the net is true, and I've never > actually cared enough about it to spend any dedicated time actually > researching it, so you may well be correct and my general feeling as well > as that table may be wrong. > > But either way, as I said, I've seen that argument made before, so > correct or misconception, it has a reasonable following who believe it to > be true. > > -- > Duncan - List replies preferred. No HTML msgs. > "Every nonfree program has a lord, a master -- > and if you use the program, he is your master." Richard Stallman > > > _______________________________________________ > Pan-users mailing list > Pan-users@nongnu.org > https://lists.nongnu.org/mailman/listinfo/pan-users > _______________________________________________ Pan-users mailing list Pan-users@nongnu.org https://lists.nongnu.org/mailman/listinfo/pan-users
