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Re: Future shell work - comments reqyuested

Robert Elz <kre%munnari.OZ.AU@localhost> wrote:
 || I think the standard says IN and ERR rather than IN and OUT for
 || this condition?!
 |It does, but we implement the latter (always have I think) - not sure
 |whether that should be changed or not, or what the effects might be.

Yes, it does.  If possible it should be changed, then.  At least
in $POSIXLY_CORRECT / posix mode.  I think the virtue would be to
be standard compliant while still being able to rock it.

 || fact it seems i never understood why this should be in and err,
 |They are the fd's that the shell (as distinct from utilities that it
 |runs, including built in ones) actually read from and write to.

Not to forget out!!

 || i think i thought use cases like "< template prog" to start into
 || interactive mode should be valid.
 |That wouldn't just start, it would start and finish.   When the shell
 |reads eof on its input file (stdin in a case like this) it exits.

My console library only supports fullscreen mode.  I don't know,
for that "< template prog 2>err.log" could very well have been
a valid interactive case, too.  It was an error to hard code that
dependency, i see this now.  For the MUA i think i should try to
end up with a logically sensitive detection of "interactive",
possibly allowing the user to force interactivity.  Unfortunately
-i is given to "ignore SIGINT", only -I could be used.

 |But perhaps I am misunderstanding what you meant?

Oh, it is ok to talk about a shell.  We are learning from that.

 |It is possible to do
 | sh -sic '. template'
 |to start an interactive shell after reading a template file (the -i works
 |there because -s is also specified.)

And there is a lot to learn.  .. Interesting, this seems to be
a speciality of the Almquist SHell, bash and mksh simply logout

  ?0[sdaoden@wales sdaoden]$ echo 'echo bla'|sh -sic 'echo da'
  Logging out ... and:
  ?0[sdaoden@wales sdaoden]$ sh -sic 'echo da'                                                                                                           
  Logging out ... and:

dash logs out only the former.

|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)

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