getting a normal ptr from shared_ptr?

c++ boost smart-pointers shared-ptr
user34537 picture user34537 · Feb 2, 2009 · Viewed 73.6k times · Source

I have something like shared_ptr<Type> t(makeSomething(), mem_fun(&Type::deleteMe)) I now need to call C styled function that requires a pointer to Type. How do I get it from shared_ptr?

Answer

Adam Rosenfield picture Adam Rosenfield · Feb 2, 2009

Use the get() method:

boost::shared_ptr<foo> foo_ptr(new foo());
foo *raw_foo = foo_ptr.get();
c_library_function(raw_foo);

Make sure that your shared_ptr doesn't go out of scope before the library function is done with it -- otherwise badness could result, since the library may try to do something with the pointer after it's been deleted. Be especially careful if the library function maintains a copy of the raw pointer after it returns.

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