Date: Fri, 4 Dec 2009 10:49:39 -0500
From: Christopher Faylor <cgf-use-the-mailinglist-please@cygwin.com>
To: cygwin@cygwin.com
Subject: Re: does LD_PRELOAD work under cygwin?
Message-ID: <20091204154939.GA29605@ednor.casa.cgf.cx>
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On Fri, Dec 04, 2009 at 01:04:33PM +0800, basic wrote:
>Hi,
>  Does LD_PRELOAD work under cygwin? I've tried the following without success:
>
>gcc test.c
>gcc -shared testlib.c -o testlib.dll
>
>LD_PRELOAD=$HOME/testlib.dll ./a.exe
>
>where test.c is:
>
>#include <fcntl.h>
>
>int main()
>{
>    open("", 1);
>    return 0;
>}
>
>
>and testlib.c is:
>
>#include <stdio.h>
>
>int open(const char *s, int i, ...)
>{
>    puts("test");
>    return 0;
>}
>
>Is there anything I'm doing wrong? Or is it just not supported?

If the above is exactly what you are doing then you're not marking
open as "dllexport" so it won't be callable.

cgf

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