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Re: Referrer key missing form os.environ dictionary?

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On Fri, Sep 27, 2013 at 12:11 AM, Grant Edwards <invalid@invalid.invalid> wrote:
> On a Unix system when you invoke a program, you "pass" it four things:
>
>  1) A dictionary where keys/values are both strings [enviornment variables]
>  2) A list of strings [command line args]
>  3) A set of open file descriptors.
>  4) The current working directory.
>
> You can provide input values to the program through any of these.
>
> For interactive programs, 2 and 3 are the most convenient.

Hrm, not sure about #3 for interactive programs, unless you
specifically mean the three standard streams. With most Unix shells,
you should be able to set environment variables:

PGUSER=fred PGPASSWORD=secret psql

Not as convenient as #2, but far easier than passing an open file
descriptor. Of course, passing file descriptors around is pretty easy
programmatically, but when you say "interactive" I assume you're
talking also about an interactive shell.

GUI interactions of course follow their own rules completely. In most
systems, it's really easy to invoke an application with one argument,
a file name; it's generally much harder to customize the arguments at
the keyboard. OS/2 had a facility for doing that. You just put square
brackets into the configured args and it'd turn it into a prompt:

--foo=bar --mode=[Choose mode, 1-3:] %*

You'd get a nice little popup with the prompt you specified, and
whatever you type gets put into the args. Haven't seen that in any
other system - at least, not as conveniently.

ChrisA

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Referrer key missing form os.environ dictionary? Νίκος <nikos.gr33k@gmail.com> - 2013-09-25 15:45 +0300
  Re: Referrer key missing form os.environ dictionary? Νίκος <nikos.gr33k@gmail.com> - 2013-09-25 16:14 +0300
  Re: Referrer key missing form os.environ dictionary? Chris “Kwpolska” Warrick <kwpolska@gmail.com> - 2013-09-25 16:01 +0200
    Re: Referrer key missing form os.environ dictionary? Νίκος <nikos.gr33k@gmail.com> - 2013-09-25 17:04 +0300
      Re: Referrer key missing form os.environ dictionary? John Gordon <gordon@panix.com> - 2013-09-25 14:26 +0000
        Re: Referrer key missing form os.environ dictionary? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-09-25 15:04 +0000
          Re: Referrer key missing form os.environ dictionary? Νίκος <nikos.gr33k@gmail.com> - 2013-09-25 18:16 +0300
            Re: Referrer key missing form os.environ dictionary? Tim Chase <python.list@tim.thechases.com> - 2013-09-25 10:42 -0500
            Re: Referrer key missing form os.environ dictionary? Denis McMahon <denismfmcmahon@gmail.com> - 2013-09-25 21:17 +0000
        Re: Referrer key missing form os.environ dictionary? Ned Batchelder <ned@nedbatchelder.com> - 2013-09-25 11:09 -0400
      Re: Referrer key missing form os.environ dictionary? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-09-25 14:52 +0000
        Re: Referrer key missing form os.environ dictionary? Νίκος <nikos.gr33k@gmail.com> - 2013-09-25 18:02 +0300
          Re: Referrer key missing form os.environ dictionary? Xaxa Urtiz <urtizvereaxaxa@gmail.com> - 2013-09-25 08:09 -0700
          Re: Referrer key missing form os.environ dictionary? Tim Chase <python.list@tim.thechases.com> - 2013-09-25 10:14 -0500
            Re: Referrer key missing form os.environ dictionary? Νίκος <nikos.gr33k@gmail.com> - 2013-09-25 18:35 +0300
        Re: Referrer key missing form os.environ dictionary? Grant Edwards <invalid@invalid.invalid> - 2013-09-25 15:18 +0000
          Re: Referrer key missing form os.environ dictionary? Νίκος <nikos.gr33k@gmail.com> - 2013-09-25 18:41 +0300
            Re: Referrer key missing form os.environ dictionary? John Gordon <gordon@panix.com> - 2013-09-25 16:27 +0000
            Re: Referrer key missing form os.environ dictionary? Grant Edwards <invalid@invalid.invalid> - 2013-09-25 18:37 +0000
          Re: Referrer key missing form os.environ dictionary? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-09-26 00:11 +0000
            Re: Referrer key missing form os.environ dictionary? Terry Reedy <tjreedy@udel.edu> - 2013-09-25 21:32 -0400
            Re: Referrer key missing form os.environ dictionary? Chris Angelico <rosuav@gmail.com> - 2013-09-26 13:25 +1000
              Re: Referrer key missing form os.environ dictionary? Grant Edwards <invalid@invalid.invalid> - 2013-09-26 14:16 +0000
            Re: Referrer key missing form os.environ dictionary? Robert Kern <robert.kern@gmail.com> - 2013-09-26 11:15 +0100
            Re: Referrer key missing form os.environ dictionary? Grant Edwards <invalid@invalid.invalid> - 2013-09-26 14:11 +0000
              Re: Referrer key missing form os.environ dictionary? Chris Angelico <rosuav@gmail.com> - 2013-09-27 01:17 +1000
                Re: Referrer key missing form os.environ dictionary? Grant Edwards <invalid@invalid.invalid> - 2013-09-26 23:27 +0000
                Re: Referrer key missing form os.environ dictionary? Chris Angelico <rosuav@gmail.com> - 2013-09-27 16:01 +1000
    Re: Referrer key missing form os.environ dictionary? Νίκος <nikos.gr33k@gmail.com> - 2013-09-25 17:07 +0300
      Re: Referrer key missing form os.environ dictionary? Robert Kern <robert.kern@gmail.com> - 2013-09-25 15:26 +0100
      Re: Referrer key missing form os.environ dictionary? John Gordon <gordon@panix.com> - 2013-09-25 14:30 +0000
      Re: Referrer key missing form os.environ dictionary? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-09-25 14:46 +0000
      Re: Referrer key missing form os.environ dictionary? Piet van Oostrum <piet@vanoostrum.org> - 2013-09-25 15:59 -0400
  Re: Referrer key missing form os.environ dictionary? John Gordon <gordon@panix.com> - 2013-09-25 14:18 +0000
    Re: Referrer key missing form os.environ dictionary? Tim Chase <python.list@tim.thechases.com> - 2013-09-25 09:58 -0500

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