[TUHS] unix v5 limitations

Noel Chiappa jnc at mercury.lcs.mit.edu
Sun Aug 10 01:32:02 AEST 2014

    > From: Mark Longridge <cubexyz at gmail.com>

    > The first problem I had was I couldn't just cp over all the
    > /usr/source/s1 files to the new drive because of "Arg list too long"

John Cowan nailed this; as an aside, I don't know about V5, but in vanilla V6
the entire argument list had to fit into one disk buffer (I would assume V5 is
the same).

The PWB changes to v6 included a rewrite of exec() to accumulate the argument
list in swap space, so it could be much longer; the maximum length was a
parameter, NCARGS, which was set to 5120 (10 blocks) by default.


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