class template
<iterator>

std::ostreambuf_iterator

template <class charT, class traits=char_traits<charT> >  class ostreambuf_iterator;
Output stream buffer iterator

Ostreambuf iterators are output iterators that write sequentially to an stream buffer.

They are constructed from a basic_streambuf object open for writing, to which they become associated.

It is defined with a behavior similar to:
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template <class charT=char, class traits=char_traits<charT> >
  class ostreambuf_iterator :
    public iterator<output_iterator_tag, charT,
                    typename traits::off_type, charT*, charT&>
{
public:
  typedef charT char_type;
  typedef traits traits_type;
  typedef typename traits::int_type int_type;
  typedef basic_streambuf<charT,traits> streambuf_type;
  typedef basic_ostream<charT,traits> ostream_type;

  ostreambuf_iterator(ostream_type& s) throw(): sbuf_(s.rdbuf()) { }
  ostreambuf_iterator(streambuf_type* s) throw(): sbuf_(s) { }
  ostreambuf_iterator& operator= (charT c)
  { if (!failed()) last=sbuf_->sputc(c); return *this; }

  ostreambuf_iterator& operator*() { return *this; }
  ostreambuf_iterator& operator++() { return *this; }
  ostreambuf_iterator& operator++(int) { return *this;}

  bool failed() const throw() { return last==traits::eof(); }

private:
  streambuf_type* sbuf_;
  charT last;
  
};

Template parameters

charT
Character type. This is the first template parameter in the basic_streambuf object.
traits
Character traits. This is the second template parameter in basic_streambuf object.

Member types

memberdefinition in ostreambuf_iteratordescription
streambuf_typebasic_streambuf<charT,traits>Type of the associated basic_streambuf object
ostream_typebasic_ostream<charT,traits>
iterator_categoryonput_iterator_tagOutput iterator
value_typevoid
char_typecharTType of the characters handled by the associated stream buffer
traits_typetraitsCharacter traits for associated stream buffer
int_typetraits::int_typeInt type to represent character values or end-of-file
difference_typevoid
pointervoid
referencevoid

Member functions

constructor
ostreambuf_iterator objects are constructed from either a basic_streambuf object or a basic_ostream object.
operator=
Writes an element into the stream buffer.
operator*
Returns the current value in the stream buffer.
operator++
Does nothing. Returns *this.
operator++(int)
Does nothing. Returns *this.
failed
Returns whether a previous writing operation failed (i.e. basic_streambuf::sputc returned traits::eof() in a previous call to operator=).

Example

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// ostreambuf_iterator example
#include <iostream>     // std::cin, std::cout
#include <iterator>     // std::ostreambuf_iterator
#include <string>       // std::string
#include <algorithm>    // std::copy

int main () {
  std::string mystring ("Some text here...\n");
  std::ostreambuf_iterator<char> out_it (std::cout); // stdout iterator

  std::copy ( mystring.begin(), mystring.end(), out_it);

  return 0;
}

Output:

Some text here...


See also