std::strstreambuf::~strstreambuf (3) - Linux Manuals

std::strstreambuf::~strstreambuf: std::strstreambuf::~strstreambuf

NAME

std::strstreambuf::~strstreambuf - std::strstreambuf::~strstreambuf

Synopsis

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.

Parameters

(none)

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.

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::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