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I have few questions on the best practices of using shared_ptr . Question 1 Is copying shared_ptr cheap? Or do I need to pass it as reference to my own helper functions and return as value? Something like, void init_fields(boost::shared_ptr<foo>& /*p_foo*/); void init_other_fields(boost::shared_ptr<foo>& /*p_foo*/); boost::shared_ptr<foo> create_foo() { boost::shared_ptr<foo> p_foo(new foo); init_fields(p_foo); init_other_fields(p_foo); } Question 2 Should I use boost::make_shared to construct a shared_ptr ? If yes, what advantages it offers? And how can we use make_shared when T doesn't have a parameter-less constructor? Question 3 How to use const foo* ? I have found two approaches for doing this. void take_const_foo(const foo* pfoo) { } int main() { boost::shared_ptr<foo> pfoo(new foo); take_const_foo(pfoo.get()); return 0; } OR typedef boost::shared_ptr<foo> p_foo; typedef const boost::shared_ptr<const foo> const_p_foo; void take_const_foo(const_p_foo pfoo) { } int main() { boost::shared_ptr<foo> pfoo(new foo); take_const_foo(pfoo); return 0; } Question 4 How can I return and check for NULL on a shared_ptr object? Is it something like, boost::shared_ptr<foo> get_foo() { boost::shared_ptr<foo> null_foo; return null_foo; } int main() { boost::shared_ptr<foo> f = get_foo(); if(f == NULL) { /* .. */ } return 0; } Any help would be great.

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