Re: [Audacity-devel] Linked libraries

[Daniel O'C. <da...@do...>]

On Thu, 1 Apr 2004 10:01, Joshua Haberman wrote:
> If I write:
>
> void foo()
> {
> 	wxString str;
> }
>
> C++ generates calls to wxString::wxString() and to
> wxString::~wxString().  There is no way this will link if the wxString
> class is not resolvable at link time.  There is no way to tell C++, at
> run time, where to find the constructor and destructor, which is what
> you would have to do to link it in at runtime.  You would be forced to
> do something like (I have no idea if you could actually make this
> work):
>
> void foo()
> {
> 	void* wxStringThisPtr;
> 	_ZN12wxStringBaseC1Emc(wxStringThisPtr);  // constructor
>
> 	int i = _ZNK12wxStringBase4findEcm(wxStringThisPtr, 'x'); // method
> call to wxStringBase::find('x');
>
> 	// ...
>
> 	_ZN12wxStringBaseD2E_(wxStringThisPtr);  // destructor, but be sure
> that all code paths call it!
> }

Mmm, but when you compile your pligin you link it to all of the libraries it 
uses, and when you dlopen() your plugin the linker will load the libraries 
that aren't already loaded and resolve the symbols.

I don't really see C++ as being that much different as long as they are built 
with compatible compilers. (for name mangling)

-- 
Daniel O'Connor software and network engineer
for Genesis Software - http://www.gsoft.com.au
"The nice thing about standards is that there
are so many of them to choose from."
  -- Andrew Tanenbaum
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