[Click] failed to load dynamic lib

[Eddie Kohler]

Hi Peter,

I'm not sure what libiw is.  Is it a C library?  Maybe it is written in 
C but they forgot to protect its headers with 'extern "C" { ... }'.  
That could cause the link error you see (C++ is giving the function a 
C++ name).  In which case you'd write

extern "C" {
#include <libiw.h>
}

or whatever.

Let us know.
Eddie


On Sep 5, 2004, at 4:59 AM, Peter De Cleyn wrote:

> Hi all,
>
> I try to build a click configuration with some elements interfacing
> with libiw. Although I managed to get these up and running a while
> ago, I keep getting undefined symbols errors when loading the script
> in to userspace mode. The machine I tried it on has recently crashed
> completely, so I installed it from scratch and maybe I forgot
> something ...
>
> The elements are in a separate dir in the elements dir. In order to
> link all object files to the package mip.uo, the make file executes as
> last
>
>  g++ -W -Wall -fno-exceptions -fno-rtti  -shared -L/usr/lib -o mip.uo
>  assowatch.uo binding.uo ... upackage.uo -liw
>
> which should link with the libiw if I'm not mistaken. assowatch is the
> element which needs the libiw
>
> ldd mip.uo gives:
>         libiw.so.25 => /usr/lib/libiw.so.25 (0x4002b000)
>         libstdc++.so.5 => /usr/lib/libstdc++.so.5 (0x40031000)
>         libm.so.6 => /lib/i686/libm.so.6 (0x400e3000)
>         libgcc_s.so.1 => /lib/libgcc_s.so.1 (0x40105000)
>         libc.so.6 => /lib/i686/libc.so.6 (0x4010f000)
>         /lib/ld-linux.so.2 => /lib/ld-linux.so.2 (0x80000000)
>
> which seems ok, but executing a script with the mip package gives me:
>
> While loading package `mip':
>   package /usr/local/lib/mip.uo: undefined symbol:
> _Z16iw_print_timevalPcPK7timeval
> requirement `mip' not available
>
> Compiling a standalone application with libiw support is not a
> problem, so I don't think its a problem of library installation.
>
> Can anyone help me with this or tell me what the exact procedures are
> to create elements that link with a shared liabrary?
>
> thanks for reading this!
>
> Peter
> _______________________________________________
> click mailing list
> click at amsterdam.lcs.mit.edu
> https://amsterdam.lcs.mit.edu/mailman/listinfo/click