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

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Mike Terry <news.dead.person.stones@darjeeling.plus.com> writes:

> On 04/12/2021 23:24, Meredith Montgomery wrote:
>> I know this isn't C.  I'm not aware of any group like
>> comp.windows.programmer.  If there is one, I'd appreciate if you set the
>> follow-up-to header.  Thank you.
>> 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.  

Sorry.  It does happen on stderr.  (And now I understand what I missed
about stdin.  See below.)  And thank you, Mike Terry.

>> I looked for a confirmation of this apparent fact and could not find
>> it.  Can you advise?  I don't see the replacements taking place; only
>> on stdout it seems to happen.  I'm not sure how to prove that.
>> Here's my attempt.  This program below shows all bytes it reads from
>> stdin.  C:\tmp>cat show-c.c #include <stdio.h> int main() { int c;
>> while ( (c = getchar()) != EOF) { printf("%d", c); } printf("\n"); }
>> C:\tmp>show-c.exe < empty.txt 10 So empty.txt must contain at least
>> byte 10.  But if Windows were fixing my line-terminations, it should
>> have added a byte 13 (on my back).
>
> This is backwards - by default Windows (well, VC++ compiler at least)
> assumes text lines end CR LF  (decimal values 13, 10).  The default
> text mode will convert CR LF to just LF, which you are seeing above - 
> presumably empty.txt has just a single empty line terminated by CR LF
> ??   If you set the stdin mode to binary you should then expect output
> "1310".

You're right.  The Windows situation is reversed when we deal with
stdin.  If I input \r\n, it replaces to \n if in _O_TEXT.  I totally
missed that indeed because --- well, it's so confusing.  Thank you.

By the way, because I used write() and saw the translations taking
place, I conclude the kernel is doing these translations, not the local
C library.

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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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