Bell Labs 'Unix' Tape from 1974 Successfully Dumped to a Tarball - Slashdot
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Archive.org now has a page with "the raw analog waveform and the reconstructed digital tape image (analog.tap), read at the Computer History Museum's Shustek Research Archives on 19 December 2025 by Al Kossow using a modified tape reader and analyzed with Len Shustek's readtape tool." A Berlin-based...
  • xthexder@l.sw0.comEnglish
    61·
    6 months ago

    I downloaded the tarball and had a look through it. Almost everything has source code included, which is pretty cool to see.

    There’s an entire C compiler from 1972, bootstrapped to be written in C. There was also a SNOBOL III compiler written in C, and a Fortran interpreter in C (only 462 lines!), and every unix command like ls,cd,echo,cat,grep,etc…

    Unsurprisingly grep was written in assembly, but it’s source is there.

    There’s also a games folder, but unfortunately these look like they’re just binaries:
    bj, chess, cubic, moo, ttt, wump
    I’ll have to load up a pdp11 emulator later to see what they are.

    • xthexder@l.sw0.comEnglish
      21·
      6 months ago

      Hello World in 1974: echo.c

      main(argc, argv)
int argc;
char *argv[];
{
	int i;

	argc--;
	for(i=1; i<=argc; i++)
		printf("%s%c", argv[i], i==argc? '\n': ' ');
}
        • xthexder@l.sw0.comEnglish
          7·
          6 months ago

          I think it’s actually quite elegant. No matter what it has to skip over argument 0 which will be the executable name echo.
          If the subtraction was removed and the loop changed to <, it would then need to do an addition or subtraction inside the loop to check if it’s the last argument.

          • palordrolap@fedia.io
            2·
            6 months ago

            The real question might be whether the compiler was smart enough to change var++ and var-- into ++var and --var when the initial values aren’t needed.

            As compiler optimisations go, it’s a fairly obvious one, but it was 1974 and putting checks like that in the compiler would increase its size and slow it down when both space and time were at a premium.

  • solrize@lemmy.mlEnglish
    19·
    6 months ago

    This is Unix v4 I think. The programs mentioned were also on later versions and I thought not hard to find. V6 sources are all online somewhere. I also expect some of those v4 programs would have been in assembler rather than C.