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Boost - shared pointer

Shared pointer is another kind of Boost library's pointer. It is similar to scoped pointer but shared pointer allows share ownership of object. We are able to assign two or more pointers pointing to the same object (it was impossible for scoped pointer).

Take a look to the example below: Output of this example is:
In point I we are initializing two shared pointers pointing to two separate instances of TestClass class, then we are printing its values in point II.

Point III shows use difference between shared pointer and scoped pointer. We are assigning two pointers to the same object of class TestClass. In this point object having testValue==5 is being destroyed (because we remove the only one pointer to that object). Also, we have two pointers pointing to objects having testValue==6 now. Note that that object will be destroyed when last shared pointer pointing to them will be destroyed (int our case it is destroyed when we are reaching end of main() function). This is key difference between scoped pointer and shared pointer.

In point IV we are printing testValues of objects which are being pointed by our both scoped pointers. Actually, it is the same object so we are getting value 6 in both cases.

Code of this example you can find in our GitHub account:
https://github.com/xmementoit/CppAdventureExamples/tree/master/boost/sharedPointer


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Comments

  1. blogReader19 January 2014 at 18:42

    Are you going to present some article describing comparison (similarities and differences) of all Boost smart pointers?

    ReplyDelete
  2. Unknown19 January 2014 at 18:43

    I scheduled your request in my articles lists so it will be released here, soon.

    ReplyDelete

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