std::ostreambuf_iterator<CharT,Traits>::ostreambuf_iterator

 

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iterator_traits input_iterator_tagoutput_iterator_tagforward_iterator_tagbidirectional_iterator_tagrandom_access_iterator_tagcontiguous_iterator_tag (C++20) iterator (deprecated in C++17)	incrementable_traits (C++20) indirectly_readable_traits (C++20) iter_value_titer_difference_titer_reference_titer_const_reference_titer_rvalue_reference_titer_common_reference_t (C++20)(C++20)(C++20)(C++23)(C++20)(C++20)
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reverse_iterator move_iterator (C++11) move_sentinel (C++20) common_iterator (C++20) counted_iterator (C++20) basic_const_iterator (C++23) const_iterator (C++23) const_sentinel (C++23) back_insert_iterator front_insert_iterator insert_iterator	make_reverse_iterator (C++14) make_move_iterator (C++11) default_sentinel_tdefault_sentinel (C++20)(C++20) unreachable_sentinel_tunreachable_sentinel (C++20)(C++20) make_const_iterator (C++23) make_const_sentinel (C++23) back_inserter front_inserter inserter
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istream_iterator ostream_iterator	istreambuf_iterator ostreambuf_iterator
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ranges::iter_move (C++20)
ranges::iter_swap (C++20)
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advance distance prev (C++11) next (C++11)	ranges::advance (C++20) ranges::distance (C++20) ranges::prev (C++20) ranges::next (C++20)
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std::ostreambuf_iterator

Member functions

ostreambuf_iterator::ostreambuf_iterator

ostreambuf_iterator::operator=

ostreambuf_iterator::operator*

ostreambuf_iterator::operator++ostreambuf_iterator::operator++(int)

ostreambuf_iterator::failed

 

	(1)
ostreambuf_iterator( streambuf_type* buffer ) throw();			(until C++11)
ostreambuf_iterator( streambuf_type* buffer ) noexcept;			(since C++11)
		(2)
ostreambuf_iterator( ostream_type& stream ) throw();				(until C++11)
ostreambuf_iterator( ostream_type& stream ) noexcept;				(since C++11)

1) Constructs the iterator with the private streambuf_type* member set to buffer and the failed() flag set to false. The behavior is undefined if buffer is a null pointer.

2) Same as ostreambuf_iterator(stream.rdbuf()).

Parameters

stream	-	the output stream whose rdbuf() will be accessed by this iterator
buffer	-	the output stream buffer to be accessed by this iterator

Example

Run this code

#include <fstream>
#include <iostream>
#include <iterator>
 
int main()
{
    const char* file = "test.txt";
    {
        std::basic_filebuf<char> f;
        f.open(file, std::ios::out);
        std::ostreambuf_iterator<char> out1(&f);
        *out1 = 'a'; // writes to file via iterator
    }
 
    // read back from the file
    char a;
    std::cout << ((std::ifstream{file} >> a), a) << std::endl;
 
    std::ostreambuf_iterator<wchar_t> out2{std::wcout};
    *out2 = L'b';
}

Output:

a
b

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR	Applied to	Behavior as published	Correct behavior
LWG 112	C++98	the requirement "the argument cannot be null" was applied to overload (2)	applies to overload (1) instead
P2325R3	C++20	default constructor was provided as C++20 iterators must be default_initializable	removed along with the requirement