std::strstreambuf::~strstreambuf
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< cpp | io | strstreambuf
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std::strstreambuf
Public member functions
strstreambuf::~strstreambuf
Protected member functions
virtual ~strstreambuf();
(deprecated in C++98) (removed in C++26)
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
(none)
[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 <iostream> #include <strstream> 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::ends ; 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::ends ; 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