Re: GNU coreutils does not work on Cygwin because of freopen() ?

[Sjors Gielen <mailinglist@dazjorz.com>]

Larry Hall (Cygwin) wrote:
> dazjorz wrote:
>> Hey all,
>>
>> I'm not very great with the inner workings of GNU or Cygwin libc, so 
>> please bear with me if I make any mistakes or misunderstandings.
>>
>> I was trying to get GNU coreutils to work on Cygwin. Maybe this seems 
>> weird to you guys, because Cygwin has coreutils, but there are a few 
>> reasons:
>> - Cygwin didn't have md5sum, GNU coreutils did (and I need md5sum)
> 
> <http://cygwin.com/cgi-bin2/package-grep.cgi?grep=bin%2Fmd5sum>
> 
> Did you miss this?

Hmm. I guess. Oh well, I didn't have md5sum before, I think :/

>> - It should work, and "Because I Can" is always a valid reason in UNIX 
>> world
>> - I'm trying to bootstrap Debian on Cygwin, and coreutils from Debian 
>> is my first try; getting coreutils from Cygwin may be done later.
>>
>> However, I noticed there are some very weird bugs happening. See for 
>> example, this bug in cat (don't look at the title of the page, I 
>> blamed bash first)
>> http://paster.dazjorz.com/?p=3845
> 
> Your example works fine for me with the latest coreutils.  Perhaps you're
> working with a buggy locally built version?
> 

Did you try with Cygwin coreutils or GNU coreutils? :)

By the way, list, I've been looking for some other things. This problem 
is caused by:
- cat calling freopen to make the handle binary (shouldn't it be binary 
in the first place? shouldn't it check if it's already opened in binary 
mode?)
- freopen() not checking if O_APPEND is set, etc. (is it possible to 
check this?)

I'll write a test case for freopen(), that shows O_APPEND is being 
missed, causing this bug.

Sjors

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