Date: Wed, 28 Sep 2005 00:05:22 EST-10EDT,10,-1,0,7200,3,-1,0,7200,3600
Subject: [UnixOS2_Archive] No. 618

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Tuesday 27 September 2005
 Number  618
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Subjects for today
 
1  Re:  help with dynamic linking : Darwin O'Connor" <doconnor at reamined.on.ca>
2  Re:  help with dynamic linking : Stefan.Neis at t-online.de
3  Re:  help with dynamic linking : Stefan.Neis at t-online.de
6  Re:  help with dynamic linking : Dave Yeo" <dave_yeo at paralynx.com>
7  Re:  help with dynamic linking : Stefan.Neis at t-online.de


**= Email   1 ==========================**

Date:  Mon, 26 Sep 2005 12:00:23 -0400
From:  "Darwin O'Connor" <doconnor at reamined.on.ca>
Subject:  Re:  help with dynamic linking

Stefan.Neis at t-online.de wrote:

> Paul Smedley schrieb:
> 
>>Hi All,
>>wondering if anyone can help me understand how to do
>>dynamic linking 
>>using gcc?
> 
> 
> The easy way is to build a static lib (.a or .lib) and run "dllar" on
> it,
> see the output of plain "dllar" for an explanation on how to use
> it (Note that you typically want to use 
>  -libf "INITINSTANCE TERMINSTANCE").
> The complicated version is to look into whatever documentation
> on "def" Files, write one, and then use "gcc -Zdll -o something.dll
> your-def-File object-Files-you-want-to-link-into-a-Dll". For details
> have a look into dllar.cmd.

def files aren't very complicated. I believe they are documented in the 
emx inf files. All you need is this:

  LIBRARY INITINSTANCE
  DATA NONSHARED
  EXPORTS
<function 1>
<function 2>
<function 3>
<global variable 1>
<global variable 2>
....






**= Email   2 ==========================**

Date:  Mon, 26 Sep 2005 18:29:54 +0200 (CEST)
From:  Stefan.Neis at t-online.de
Subject:  Re:  help with dynamic linking

Darwin O'Connor schrieb:
> def files aren't very complicated.
(snipp)
>   LIBRARY INITINSTANCE
>   DATA NONSHARED
>   EXPORTS
> <function 1>
> <function 2>
> <function 3>
> <global variable 1>
> <global variable 2>

However, for large libraries, generating the list of
functions and global variables is not really fun, which
is why I prefer to delegate that job to dllar. It's essentially
using emxexport(?) to generate those lists, generates
the def File and calls
    gcc -Zdll -o dll-name generated-def-file object-files
so why would anybody do all this by hand? Of course,
if you need to add ordinals to the functions/variables
that are compatible  with the ordinals of earlier versions,
you _do_ need to manually fix the def file, but normally
we shouldn't need to touch it...

         Regards,
                 Stefan


**= Email   3 ==========================**

Date:  Mon, 26 Sep 2005 17:14:16 +0200 (CEST)
From:  Stefan.Neis at t-online.de
Subject:  Re:  help with dynamic linking

Paul Smedley schrieb:
> Hi All,
> wondering if anyone can help me understand how to do
> dynamic linking 
> using gcc?

The easy way is to build a static lib (.a or .lib) and run "dllar" on
it,
see the output of plain "dllar" for an explanation on how to use
it (Note that you typically want to use 
 -libf "INITINSTANCE TERMINSTANCE").
The complicated version is to look into whatever documentation
on "def" Files, write one, and then use "gcc -Zdll -o something.dll
your-def-File object-Files-you-want-to-link-into-a-Dll". For details
have a look into dllar.cmd.

        Regards,
                 Stefan


**= Email   6 ==========================**

Date:  Mon, 26 Sep 2005 16:54:40 -0800
From:  "Dave Yeo" <dave_yeo at paralynx.com>
Subject:  Re:  help with dynamic linking

On Mon, 26 Sep 2005 20:26:00 +0930, Paul Smedley wrote:

>Hi All,
>wondering if anyone can help me understand how to do dynamic linking 
>using gcc?
>
>It's be nice to make use of dlls instead of using static linking :)

Surprisingly configure --enable-shared --disable-static often ends up with a DLL. Needs
AC_LIBTOOL_WIN32_DLL
AC_PROG_LIBTOOL
in configure.in and helps to use Andreas port of libtool.
Dave



**= Email   7 ==========================**

Date:  Tue, 27 Sep 2005 11:48:12 +0200 (CEST)
From:  Stefan.Neis at t-online.de
Subject:  Re:  help with dynamic linking

Paul Smedley wrote:

> It's be nice to make use of dlls instead of using static
> linking :)

Actually, no, not really. Every application coming with its
own version of certain DLLs (which still are limited to 8 letter
names) which are mutually incompatible between different
apps is causing problems all the time (see discussion about
iconv.dll and/or intl.dll, about problems with X11 vs. Innotek
versions of jpeg.dll and X11 vs. somebody elses versions of
zlib.dll). Using "export by name" for new DLLs would help
avoid some of these problems in the future, though.

         Regards,
                  Stefan