[TUHS] First appearance of named pipes

Noel Chiappa jnc at mercury.lcs.mit.edu
Sat Mar 7 08:44:31 AEST 2020

    > From: Paul Ruizendaal

    > The paper is from late 1981. ... When did FIFO's become a
    > standard Unix feature?

Err, V4? :-) At least, that's when pipes arrived (I think - we don't have V4
sources, but there are indications that's when they appeared), and a pipe is a
FIFO. RAND ports just allowed (effectively) a pipe to have a name in the file

The implementation of both is pretty straight-forward. A pipe is just a file
which has a maximum length, after which the writer is blocked. A port is
just a pipe (it uses the pipe code) whose inode appears in the file system.

    > From: Clem Cole

    > I think the code is on one of the 'USENIX' tapes in Warren's archives.

Doc is here:


and sources for all that are here:


(port.c is in 'dmr', not 'ken'where it should be).


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