Re: [Boost-users] [serialization] seriazation from base pointer /Runtime Casting

From: Robert Ramey (ramey_at_[hidden])
Date: 2005-12-05 23:32:09

It SHOULD work but this is an area still in flux.

You might expand on the explanation of how it fails:

Some observations:

There should be no need to include the header 
<boost/serialization/serialization.hpp>

The serialization code will be instantiated only when code like ar << 
session_record
is encountered.  Since your DLL code doesn't include your any archives no 
code
is generated.

The first step to making this work is to look at the demo which
compiles serialization code in separate modules.  This shows
how to instantiate the required code.  Also look at
polymorphic archives which permit application
code to be compiled to a common interface.

Good Luck

Robert Ramey

__PPS__ wrote:
> is it possible to have this exported from dll:
>
> ///export.h///
>
> #include <boost/serialization/serialization.hpp>
>
> class session_record {
>   virtual void print_on(std::ostream& os) const = 0;
>   friend std::ostream & operator<<(std::ostream& os, const
> session_record& sr){
>     sr.print_on(os);
>     return os;
>   }
> public:
>   friend class boost::serialization::access;
>   virtual ~session_record();
>   template<class Archive> void serialize(Archive & ar, const unsigned
> int file_version){}
>   operator session_record *();
> };
>
> void serialize(session_record* derived, const char* file_name);
> session_record* deserialize(const char* file_name);
>
> ///end of export.h///
>
> and then in an application (linked to the dll that exports all from
> export.h) I create derived classes from session_record and serialize
> or deserialize them to/from files using the two exported free
> functions. I followed exactly steps in "Runtime Casting" of the
> manual, but it doesn't work. So... is it really runtime if it doesn't
> work this way - it only works if all the derived classes are known &
> registered at the time of compilation of the two functions. All that
> worked well if everything from export.h was linked statically, but
> not dynamically
>
> Am I doing something wrong with all that stuff??
> thanks