Re: Dumb linker/loader question

[walt <wa1ter@xxxxxxxxxxxxx>]

Max Okumoto wrote:
> Simon 'corecode' Schubert wrote:
>
> > On 15.01.2005, at 20:52, Chris Pressey wrote:
> >
> > > > I'm clearly lacking some basic understanding of how this whole
> > > > thing works.  How can code that uses the header files from a
> > > > library compile *and* link successfully without that library?

> > > In brief: because linking to shared objects (.so's) happens only when
> > > the program is loaded, i.e. at runtime... 

> > I think that's not 100% true. It won't work with executables because 
> > the linker indeed looks for the functions, if they exist in the shared 
> > object you're linking to. But it can't do so if you build a shared 
> > objects yourself. Then it just takes it for granted that the functions 
> > you are referring to will be present at load time.
> >
> > cheers
> >   simon

> The linker (/usr/bin/ld) need either a foo.a or a foo.so file.  The 
> header is not sufficent.  There must be a library laying around in your
> link path.  Try and run ldd on the binary and see what it thinks it is
> using.

Yours responses led me to the problem (which is obvious now, of course).

Thanks for the great help!  Meanwhile, I notice that Roland already
finished the override for me -- but I'm amazed how much of it I got
right -- I just left some things out ;o)