From: Justin Bonnar <jbonnar@...>
Date: 2006-09-13T17:00:57+09:00
Subject: Re: Wrapping a C Library: Allocation and duplication issues

Acutally, I'm not a C or Ruby/C guru, but would any of the following be 
possible?

- Wrapping a null pointer in the allocation function, and then modifying 
the DATA object to use the pointer returned by the 
librdf_new_classname() call.

- Creating a pointer to the data structure, and then setting it's value 
to the pointer returned by the librdf_new_classname() call.

The following code compiles and runs, but doesn't seem to work correctly 
(other functions that access the C structure wrapped by the object 
behave strangely.)

  static VALUE URI_alloc(VALUE klass)
  {
    librdf_uri* uri;
    return Data_Wrap_Struct(klass, 0, librdf_free_uri, uri);
  }

  static VALUE URI_initialize(VALUE self, VALUE uri_string)
  {
    librdf_uri* uri;
    Data_Get_Struct(self, librdf_uri, uri);
    uri = librdf_new_uri(World, StringValuePtr(uri_string));
    return self;
  }

Thanks,
Justin

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