Re: [PATCH] index-pack usage of mmap() is unacceptably slower on many OSes other than Linux

From: Junio C Hamano <junkio@cox.net>
Date: Dec 19, 2006, 19:00 UTC
Message-ID: <7vk60npv7x.fsf@assigned-by-dhcp.cox.net>
In-Reply-To: <Pine.LNX.4.64.0612191027270.18171@xanadu.home>

Nicolas Pitre <nico@cam.org> writes:

> OK looks like this has been sorted out while I was away.  Good!
>
> This is Linus's patch plus a few cosmetic changes.

Not a complaint but rather a request for free education ;-).

Show 19 quoted lines

> diff --git a/index-pack.c b/index-pack.c
> index 6d6c92b..e08a687 100644
> --- a/index-pack.c
> +++ b/index-pack.c
> @@ -1,3 +1,8 @@
> +#define _XOPEN_SOURCE 500
> +#include <unistd.h>
> +#include <sys/time.h>
> +#include <signal.h>
> +
>  #include "cache.h"
>  #include "delta.h"
>  #include "pack.h"
> @@ -6,8 +11,6 @@
>  #include "commit.h"
>  #include "tag.h"
>  #include "tree.h"
> -#include <sys/time.h>
> -#include <signal.h>

Most of the rest of the sources seem to do our includes first and source-file specific system includes at the end. What's the rationale for this change?

Do we need _XOPEN_SOURCE=500 because pread() is XSI?

Also nobody other than convert-objects.c has _XOPEN_SOURCE level specified. If _XOPEN_SOURCE matters I wonder if we should do so in some central place to make it consistent across source files?