From: "Iñaki Baz Castillo" <ibc@...>
Date: 2012-03-12T05:02:03+09:00
Subject: Re: [C extension] How to detect Linux Kernel and glibc version?

2012/3/8 Eric Wong <normalperson@yhbt.net>:
> I assume you meant ext/kgio/missing_accept4.h and not the actual diff:
>
> $ sed -ne 8,14p < ~/kgio/ext/kgio/missing_accept4.h
> #    if (02000000 == O_NONBLOCK)
> #      define SOCK_CLOEXEC 1
> #      define SOCK_NONBLOCK 2
> #    else
> #      define SOCK_CLOEXEC 02000000
> #      define SOCK_NONBLOCK O_NONBLOCK
> #    endif
>
> I'm just defining SOCK_* macros so the wrapper function has a way
> of making sense of those flags and expose an interface similar
> to the accept4() syscall.  Those macros eventually get defined
> to the corresponding Kgio::SOCK_* constants in Ruby.
>
> This compatibility workaround of defining macros that look like
> system-provide ones is only safe for use private headers, though.
> (Don't do anything crazy like resolve the Ruby constants to
>  Integers in your source and expect those Integers to work across
>  upgrades/different platforms)

Clear, thanks a lot.

-- 
Iñaki Baz Castillo
<ibc@aliax.net>