Re: The joy of pipes

Louis Krupp <lkrupp@invalid.pssw.com.invalid> writes:

On 11/15/2024 12:49 AM, 186282@ud0s4.net wrote:
>
 On 11/14/24 9:05 PM, Lawrence D'Oliveiro wrote:
>
 On Thu, 14 Nov 2024 16:09:07 -0800, John Ames wrote:
>
 (I think it was a topic shift to applications of *nix pipes...?)
>
 Oh shelly boy, the pipes, the pipes are calling ...
>
   Pipes are good.
>
   But, really, they're just temp files the parent
   process can access.
>
Pipes *could* be implemented with temporary disk files, at least to an
extent, but as far as I can tell, they're not.

“Temporary files the parent can access” is not a good model for a couple
of reasons:

* The semantics are different. Bytes read from a regular file are still
  there to be read again if you rewind the file; bytes read from a pipe
  are gone. Empty/full files behave differently to empty/full pipes.

* Temporary regular files can already be accessed by other processes by
  name, by file descriptor inheritance, or file descriptor passing.

--
https://www.greenend.org.uk/rjk/