Noel Chiappa jnc at mercury.lcs.mit.edu
Thu Mar 22 00:51:41 AEST 2018

    > From: "Steve Johnson"

So, I have this persistent memory that I read, in some early Multics (possibly
CTSS, but ISTR it was Multics) document, a footnote explaining the origin of
the term 'daemon'. I went looking for it, but couldn't find it in a 'quick'

I did find this, though, which is of some interest: R. A. Freiburghouse, "The
Multics PL/1 Compiler" (available online here:


if anyone is interested).

    > There was a group that was pushing the adoption of PL/1, being used to
    > code Multics, but the compiler was late and not very good and it never
    > really caught on.

So, in that I read:

  The entire compiler and the Multics operating system were written in EPL, a
  large subset of PL/1 ... The EPL compiler was built by a team headed by
  M. D. McIlroy and R. Morris ... Several members of the Multics PL/1 project
  modified the original EPL compiler to improve its object code performance,
  and utilized the knowledge acquired from this experience in the design of
  the Multics PL/1 compiler.

The EPL compiler was written when the _original_ PL/1 compiler (supposedly
being produced by a consulting company, Digitek) blew up. More detail is
available here:


I assume it's the Digitek compiler you were thinking of above?


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