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

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Manfred <noname@add.invalid> writes:

> On 12/6/2021 1:34 PM, Ben Bacarisse wrote:
>> Bonita Montero <Bonita.Montero@gmail.com> writes:
>> 
>>> Am 06.12.2021 um 11:36 schrieb Ben Bacarisse:
>>>> John Forkosh <forkosh@panix.com> writes:
>>>>
>>>>> Bonita Montero <Bonita.Montero@gmail.com> wrote:
>>>>>> Meredith Montgomery wrote:
>>>>>>>
>>>>>>> Windows provides me _setmode(), with which I can put stdout on
>>>>>>> _O_BINARY.  It then stops replacing \n with \r\n.  However, it seems
>>>>>>> that Windows does not do any such replacements on stdin and stderr.  I
>>>>>>> looked for a confirmation of this apparent fact and could not find it.
>>>>>    <<snip>>
>>>>>>
>>>>>> Check the output of this in your hex-editor:
>>>>>>
>>>>>> #include <stdio.h>
>>>>>> #include <fcntl.h>
>>>>>> #include <io.h>
>>>>>> #include <stdlib.h>
>>>>>>
>>>>>> int main( int argc, char **argv )
>>>>>> {
>>>>>>          if( argc >= 2 && _setmode( _fileno( stderr ), _O_BINARY ) == -1 )
>>>>>>                  return EXIT_FAILURE;
>>>>>>          fprintf( stderr, "it works !\n" );
>>>>>> }
>>>>>>
>>>>>> Without a commandline-parameter you've 0x0D, 0x0A
>>>>>> as a line-separator, with you've got only 0x0A.
>>>>
>>>> Summary: making stdout binary.
>>>>
>>>>> Yeah, that's more or less what I've been doing, but is there
>>>>> maybe a portable way to do it, i.e., for programs intended to
>>>>> run both under windows and linux?
>>>>
>>>> There's a standard function that /could/ do it, but it is allowed to be
>>>> no-op.  I don't have access to a Windows programming environment, so I
>>>> can't check it:
>>>>
>>>>     freopen(NULL, "ab", stdout);
>>>>
>>>> (or maybe "wb", it's the b you want of course).
>>> Doesn't work with either wb or ab:
>>>
>>> #include <stdio.h>
>>> #include <stdlib.h>
>>>
>>> int main( int argc, char **argv )
>>> {
>>> 	if( argc < 2 )
>>> 		return EXIT_FAILURE;
>>> 	FILE *pfErr = freopen( NULL, argv[1], stderr);
>>> 	printf( "%p", (void *)pfErr );
>>> }
>>>
>>>   en.cppreference.com says:
>>>
>>> "Microsoft CRT version of std::freopen does not support any mode
>>>   changes when filename is a null pointer and treats this as an
>>>   error (see documentation). A possible workaround is the non
>>>   -standard function _setmode()."
>> I feared this would be the case.  It was many years ago when this last
>> came up.  Maybe some alternative C library has made what appears to be
>> the trivial modification to make it work?
>> Anyway, if the most widely used C library does not support it, it's not
>> portable in any useful way.
>
> I'm not sure the Microsoft CRT is the most widely used library (I'd
> say it is on Windows, in general I think it isn't), but it's used
> widely enough to make portability an issue, sure.

I meant "on Windows".  On, say, Linux, I would think it does not matter
if freopen(NULL, "wb", stdout) fails, since streams are already binary.

-- 
Ben.

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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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