Re: interactive shell detection in shrc

Steffen Nurpmeso wrote in
 <20240927224352.XbfXbbOA@steffen%sdaoden.eu>:
 |Robert Elz wrote in
 | <[email protected]>:
 | ...
 ||| I guess to be entirely POSIX compatible my test should include:
 |||
 |||  tty >/dev/null 2>&1 && tty <&1 >/dev/null 2>&1 &&
 ||
 ||The second of those would need to be testing (the pre-redirected)
 ||stderr, not stdout, interactive shells don't care where stdout has
 ||been sent (though the user probably does).
 ||
 ||But as Steffen (kind of) indicated, "test -t 0 && test -t 2" is
 ||probably an easier way than using tty.

I must apologise, that "recently" was in 2017, over seven years
ago!  (But dash will change no sooner but with the next release,
i think .. actually not in git as of 2024-07-28.  Will ask..)

  commit a373e69a196cd8d45f2806d805e548fa65a982ba
  Author:     kre <[email protected]>
  AuthorDate: 2017-07-24 12:35:37 +0000
  Commit:     kre <[email protected]>
  CommitDate: 2017-07-24 12:35:37 +0000

      PR standards/52406

      Absent other information, the shell should be interactive if reading
      from stdin, and stdin and stderr are ttys, not stdin and stdout.

      So sayeth the great lord posix.

--steffen
|
|Der Kragenbaer,                The moon bear,
|der holt sich munter           he cheerfully and one by one
|einen nach dem anderen runter  wa.ks himself off
|(By Robert Gernhardt)