Date: Fri, 13 Jan 2006 11:13:40 -0500
From: Christopher Faylor <cgf-no-personal-reply-please AT cygwin DOT com>
To: cygwin AT cygwin DOT com
Subject: Re: Define _POSIX_SOURCE in cygwin's features.h?
Message-ID: <20060113161340.GB17052@trixie.casa.cgf.cx>
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References: <20060112173104 DOT GA30011 AT trixie DOT casa DOT cgf DOT cx> <43C7BD94 DOT 7090704 AT byu DOT net>
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On Fri, Jan 13, 2006 at 07:47:48AM -0700, Eric Blake wrote:
>Now what does this all mean to cygwin?  Most apps don't care about strict
>compliance - they are more than willing to use extensions if it makes it
>easier to get the job done, so most apps don't define _POSIX_SOURCE or
>_POSIX_C_SOURCE before including headers.  I agree with Samuel's
>conclusion - we can use the Linux trick of having a default configuration
>of gcc that turns on _GNU_SOURCE (itself a feature test, that turns on all
>other extensions), provided that gcc can also be told to be strictly
>compliant to a given standard (gcc's -ansi flag, among others).

Thank you for your feedback.  I was just going to silently digest this but
I can't let this particular one slide.

I don't see how you credit *Samuel* with any conclusions other than the
one that anyone who used _POSIX_SOURCE in source code was stupid and
that I needed to read a book on posix.  After making those observations
for a couple of paragraphs he quoted a snippet of a header file that *I*
included and said "Well, that's ok then".  I'm glad to have his
permission on this, though.

So, let me state a few things:

0) It is cygwin's goal to emulate linux (as per the cygwin web page).

1) linux defines _POSIX_SOURCE by default unless specific gcc command
line options are specified (as per the code snippet that I posted).

2) I want cygwin to be *more* like linux (as per my repeated assertions
in this thread and elsewhere).

3) The fact that the cygwin header files are currently inconsistent, and
probably wrong, wrt _POSIX_SOURCE does not preclude fixing them to make
them more like linux.

Conclusion: newlib's headers are not close enough to glibc headers and
that is what is causing people problems.

Task for 1.5.20: Make cygwin's header files more like the linux header
files.

I'm sorry that my goals here were not clearer from my original message.
I don't need anymore feedback about this.

cgf

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