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Re: ot: on stdin, stdout, stderr and crlf on windows

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On 07/12/2021 01:11, John Forkosh wrote:
> Ben Bacarisse <ben.usenet@bsb.me.uk> wrote:

>> Anyway, if the most widely used C library does not support it, it's not
>> portable in any useful way.
> 
> Thanks, Ben and Bonita (and Malcom and Manfred), yeah I also "feared
> this would be the case", i.e., no portable solution like freopen(),
> which would be syntactically identical on all platforms and "just work",
> whether needed (windows) or not (linux).
> 
> By the way, at least at the time when I wrote that stackexchange post,
> some windows C compilers used _setmode(_fileno(stderr),_O_BINARY)
> like Bonita said, but some others used setmode(fileno(stderr),O_BINARY).
> So additional #ifdefs needed to resolve that. And I'm also not sure
> that _MSC_VER always identifies all windows C compilers. The elaborate
> #ifdefs illustrated on that stackexchange post were what I ended up
> with to accommodate all the variations I'd encountered at the time
> I wrote it. So I was hoping to find some less elaborate and fewer
> lines of gobbledy-gook code, if not entirely 100% portable, to identify
> and handle all possible windows situations.
> 

Every Windows system comes with a C library called msvcrt.dll. And 
msvcrt.dll (usually located in C:\windows\system32) defines _setmode.

That means I can reliably call that function even from a script language 
as follows:

     importdll msvcrt=
         clang function _setmode(int32,int32)int32
     end

     println _setmode(1,32768)     # 1=stdout, 32768=O_BINARY

Ironically, this appears difficult to do from C!

First because it's hard to pinpoint that function in that specific 
library. But also because it needs to be the same library that is used 
by your *printf and other functions, otherwise you're setting the mode 
of the wrong library.

You would need, somehow, to specifically link with this library, but 
even then, there might be shortcomings: some parts of it might too slow; 
some other functions could be missing.

(With my script, the call works both for native 'print' which eventually 
calls 'printf' of the C library dynamically linked to the interpreter 
executable, and for direct 'printf' calls within that msvcrt loaded by 
the script (printf declaration and use not shown).

I expected there to be two instances of msvcrt, but presumably the OS 
sees them as both invoked by the same program so they must share data.)

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ot: on stdin, stdout, stderr and crlf on windows Meredith Montgomery <mmontgomery@levado.to> - 2021-12-04 20:24 -0300
  Re: ot: on stdin, stdout, stderr and crlf on windows Mike Terry <news.dead.person.stones@darjeeling.plus.com> - 2021-12-05 00:01 +0000
  Re: ot: on stdin, stdout, stderr and crlf on windows Mike Terry <news.dead.person.stones@darjeeling.plus.com> - 2021-12-05 00:13 +0000
    Re: ot: on stdin, stdout, stderr and crlf on windows Meredith Montgomery <mmontgomery@levado.to> - 2021-12-04 23:09 -0300
      Re: ot: on stdin, stdout, stderr and crlf on windows Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-12-04 18:27 -0800
      Re: ot: on stdin, stdout, stderr and crlf on windows Mike Terry <news.dead.person.stones@darjeeling.plus.com> - 2021-12-05 03:33 +0000
        Re: ot: on stdin, stdout, stderr and crlf on windows Meredith Montgomery <mmontgomery@levado.to> - 2021-12-05 09:17 -0300
  Re: ot: on stdin, stdout, stderr and crlf on windows Bonita Montero <Bonita.Montero@gmail.com> - 2021-12-05 15:04 +0100
  Re: ot: on stdin, stdout, stderr and crlf on windows Bonita Montero <Bonita.Montero@gmail.com> - 2021-12-05 15:13 +0100
    Re: ot: on stdin, stdout, stderr and crlf on windows John Forkosh <forkosh@panix.com> - 2021-12-06 08:20 +0000
      Re: ot: on stdin, stdout, stderr and crlf on windows Bonita Montero <Bonita.Montero@gmail.com> - 2021-12-06 09:45 +0100
      Re: ot: on stdin, stdout, stderr and crlf on windows Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-12-06 10:36 +0000
        Re: ot: on stdin, stdout, stderr and crlf on windows Bonita Montero <Bonita.Montero@gmail.com> - 2021-12-06 13:03 +0100
          Re: ot: on stdin, stdout, stderr and crlf on windows Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-12-06 12:34 +0000
            Re: ot: on stdin, stdout, stderr and crlf on windows Manfred <noname@add.invalid> - 2021-12-06 14:38 +0100
              Re: ot: on stdin, stdout, stderr and crlf on windows Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2021-12-06 06:00 -0800
                Re: ot: on stdin, stdout, stderr and crlf on windows Manfred <noname@add.invalid> - 2021-12-06 18:59 +0100
              Re: ot: on stdin, stdout, stderr and crlf on windows Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-12-06 17:08 +0000
                Re: ot: on stdin, stdout, stderr and crlf on windows scott@slp53.sl.home (Scott Lurndal) - 2021-12-06 17:18 +0000
            Re: ot: on stdin, stdout, stderr and crlf on windows John Forkosh <forkosh@panix.com> - 2021-12-07 01:11 +0000
              Re: ot: on stdin, stdout, stderr and crlf on windows Bart <bc@freeuk.com> - 2021-12-07 09:56 +0000
                Re: ot: on stdin, stdout, stderr and crlf on windows John Forkosh <forkosh@panix.com> - 2021-12-08 08:13 +0000
  Re: ot: on stdin, stdout, stderr and crlf on windows Tim Rentsch <tr.17687@z991.linuxsc.com> - 2021-12-10 01:10 -0800
    Re: ot: on stdin, stdout, stderr and crlf on windows gazelle@shell.xmission.com (Kenny McCormack) - 2021-12-10 11:00 +0000

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