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...
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  • xthexder@l.sw0.comEnglish
    4 months

    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
      4 months

      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.