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std::strstreambuf::freeze(3)   C++ Standard Libary  std::strstreambuf::freeze(3)

NAME
     std::strstreambuf::freeze - std::strstreambuf::freeze

Synopsis
	void freeze( bool freezefl = true );  (deprecated in C++98)
					      (removed in C++26)

	If  the  buffer  uses  dynamic allocation, sets the frozen status of the
     stream to
	freezefl.

	While the stream is frozen, overflow() will not  reallocate  the  buffer
     and the
	destructor  will  not  deallocate  the	buffer (thereby causing a memory
     leak).

Parameters
	freezefl - new value to set the freeze status to

Return value
	(none)

Notes
	Every call to str() freezes the stream to preserve the validity  of  the
     pointer it
	returns. To allow the destructor to deallocate the buffer, freeze(false)
     needs to be
	called explicitly.

Example
	In  this  example, initial allocation of the underlying array was for 16
     bytes.

     // Run this code

      #include <iostream>
      #include <strstream>

      int main()
      {
	  {
	      std::strstream dyn; // dynamically-allocated read/write buffer
	      dyn << "Test: " << 1.23; // note: no std::ends to demonstrate  ap-
     pend behavior
	      std::cout  << "dynamic buffer holds " << dyn.pcount() << " charac-
     ters: '";
	      std::cout.write(dyn.str(), dyn.pcount()) << "'\n";
	      // the buffer is now frozen, further  output  will  not  make  the
     buffer grow
	      dyn  << "more output, hopefully enough to run out of the allocated
     space"
		  << std::ends;
	      std::cout << "After more output, it holds "
			<< dyn.pcount() << "  characters:  '"  <<  dyn.str()  <<
     "'\n";
	      dyn.freeze(false); // unfreeze before destructor
	  } // memory freed by the destructor

	  {
	      char arr[20];
	      std::ostrstream st(arr, sizeof arr); // fixed-size buffer
	      st << 1.23; // note: no std::ends to demonstrate append behavior
	      std::cout << "static buffer holds "
			<< st.pcount() << " characters: '";
	      std::cout.write(st.str(), st.pcount());
	      std::cout << "'\n";
	      st  <<  "more output, hopefully enough to run out of the allocated
     space"
		 << std::ends;
	      std::cout << "static buffer holds "
			<< st.pcount() << " characters: '";
	      std::cout.write(st.str(), st.pcount());
	      std::cout << "'\n";
	  } // nothing to deallocate, no need to unfreeze,
      }

Output:
      dynamic buffer holds 10 characters: 'Test: 1.23'
      After more output, it holds 16 characters: 'Test: 1.23more o'
      static buffer holds 4 characters: '1.23'
      static buffer holds 20 characters: '1.23more output, hop'

See also
	freeze	     disables/enables automatic reallocation
		     (public member function of std::strstream)
	freeze	     disables/enables automatic reallocation
		     (public member function of std::ostrstream)
	destructor   destructs a strstreambuf  object,	optionally  deallocating
     the character
	[virtual]    array
		     (virtual public member function)
	overflow      appends a character to the output sequence, may reallocate
     or initially
	[virtual]    allocate the buffer if dynamic and not frozen
		     (virtual protected member function)

http://cppreference.com 	   2024.06.10	    std::strstreambuf::freeze(3)
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