std::strstreambuf::~strstreambuf - cppreference.com

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# std::strstreambuf::~strstreambuf

From cppreference.com
< cpp‎ | io‎ | strstreambuf

virtual ~strstreambuf(); |  |

Destroys a `std::strstreambuf` object. if the object is managing a dynamically-allocated buffer (the buffer state is "allocated") and if the object is not frozen, then deallocates the buffer using the deallocation function provided at construction or delete[] if none was provided.

### [edit] Parameters

(none0

### [edit] Notes

This destructor is typically called by the destructor of std::strstream

If str() was called on a dynamic strstream and freeze(false) was not called after that, this destructor leaks memory.

### [edit] Example

Run this code

    #include <strstream>
    #include <iostream>

    void* my_alloc(size_t n)
    {
        std::cout << "my_alloc(" << n << ") called\n";
        return new char[n];
    }

    void my_free(void* p)
    {
        std::cout << "my_free() called\n";
        delete[] (char*)p;
    }

    int main()
    {
        {
            std::strstreambuf buf(my_alloc, my_free);
            std::ostream s(&buf);
            s << 1.23;
            std::cout << buf.str() << '\n';
            buf.freeze(false);
        } // destructor called here, buffer deallocated

        {
            std::strstreambuf buf(my_alloc, my_free);
            std::ostream s(&buf);
            s << 1.23;
            std::cout << buf.str() << '\n';
    //        buf.freeze(false);
        } // destructor called here, memory leak!
    }

Output:

    my_alloc(4096) called
    1.23
    my_free() called
    my_alloc(4096) called
    1.23

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