Re: [Xenomai-help] libnative and libxenomai dependy problem

[Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>]

On 04/25/2012 12:05 PM, Willy Lambert wrote:
> 2012/4/23 Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>:
>> On 04/23/2012 03:57 AM, Willy Lambert wrote:
>>> 2012/4/23 Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>:
>>>> On 04/23/2012 01:57 AM, Willy Lambert wrote:
>>>>> Hi,
>>>>>
>>>>> I just run into the same kind of problem of a one year old discussion :
>>>>> http://www.mail-archive.com/xenomai@xenomai.org
>>>>>
>>>>> having such kind of errors :
>>>>> /usr/lib/libnative.so.3: undefined symbol: xeno_current_mode_key
>>>>> I have a xenomai 2.6.0 recompiled from sources with the --dl-open
>>>>> option enabled.
>>>>> root@domain.hid):~# cat /proc/xenomai/version
>>>>> 2.6.0
>>>>>
>>>>>
>>>>> I re-post something because I'm not sure it is up to date and as I
>>>>> have the next version I am suprised the problem still arises
>>>>>
>>>>> I have 2 question :
>>>>> _ did I missconfigured something in my compiller flags or linking ?
>>>>> _ are the solutions of last thread still up to date ?
>>>>>
>>>>
>>>> You need to dlopen libxenomai in order for dlopen(libnative) to succeed.
>>>>
>>>> --
>>>>                                                                Gilles.
>>>
>>> In fact I never called dlopen(libnative) myself. It is done in a
>>> library to which I am linked. Do I have a to dlopen it in my personnal
>>> code ?
>>>
>> you have to manage for dlopen(libxenomai) to be called before
>> dlopen(libnative), and with the RTDL_GLOBAL flag so that libnative will
>> find the symbols defined by libxenomai.
>>
>> --
>>                                                                Gilles.
> 
> Thanks for support. In fact I am not using dlopen directly (dynamic
> linking)

dynamic linking and dlopen are two different things. When you use
dynamic linking, dlopen is not used underneath. dlopen is part of the
libdl library, which you do not even need for dynamic linked appications.

> but in ordering the linking I got it working (without having
> to set the flag which might be set underneath).
> I'm quite surprised thougth that is is a "soft" dependency. Is it my
> bad not having used --xeno-config directly ? (I use a shortcut because
> all the stuff is under CMake and I am not an expert with it).

Yes, you should use xeno-config. The reason why libxenomai is not made a
dependency of libnative is that the straight-forward solution to do this
with the version of libtool we use breaks badly when cross-compiling.

-- 
					    Gilles.