std::return_temporary_buffer

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Defined in header <memory>
template< class T >
void return_temporary_buffer( T* p );
(deprecated in C++17)
(removed in C++20)

Deallocates storage previously allocated with std::get_temporary_buffer.

Parameters

p - the pointer previously returned by std::get_temporary_buffer and not invalidated by an earlier call to return_temporary_buffer

Return value

(none)

Exceptions

Throws nothing.

Example

#include <algorithm>
#include <iostream>
#include <memory>
#include <string>
#include <iterator>
 
int main()
{
    const std::string s[] = {"string", "1", "test", "..."};
    const auto p = std::get_temporary_buffer<std::string>(4);
    // requires that p.first is passed to return_temporary_buffer
    // (beware of early exit points and exceptions)
 
    std::copy(s, s + p.second,
              std::raw_storage_iterator<std::string*, std::string>(p.first));
    // has same effect as: std::uninitialized_copy(s, s + p.second, p.first);
    // requires that each string in p is individually destroyed
    // (beware of early exit points and exceptions)
 
    std::copy(p.first, p.first + p.second,
              std::ostream_iterator<std::string>{std::cout, "\n"});
 
    std::for_each(p.first, p.first + p.second, [](std::string& e) {
        e.~basic_string<char>();
    }); // same as: std::destroy(p.first, p.first + p.second);
 
    std::return_temporary_buffer(p.first);
}

Output:

string
1
test
...

See also

(deprecated in C++17)(removed in C++20)
obtains uninitialized storage
(function template)