std::basic_streambuf::setp

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< cpplrm; | iolrm; | basic streambuf
C++
Input/output library
std::basic_streambuf
Public member functions
Locales
Positioning
Get area
Put area
Putback
Protected member functions
(C++11)
(C++11)
Locales
Positioning
Get area
Put area
basic_streambuf::setp
Putback
void setp( char_type* pbeg, char_type* pend );

Sets the values of the pointers defining the put area. Specifically, after the call pbase() == pbeg, pptr() == pbeg, epptr() == pend

Parameters

pbeg - pointer to the new beginning of the put area
pend - pointer to the new end of the put area

Return value

(none)

Example

Run this code
#include <iostream>
#include <array>

// Buffer for std::ostream implemented by std::array
template<std::size_t SIZE, class CharT = char>
class ArrayedStreamBuffer : public std::basic_streambuf<CharT>
{
public:
    using Base = std::basic_streambuf<CharT>;
    using char_type = typename Base::char_type;

    ArrayedStreamBuffer() : buffer_{} // value-initialize buffer_ to all zeroes
    {
        Base::setp(buffer_.begin(), buffer_.end()); // set std::basic_streambuf
            // put area pointers to work with 'buffer_'
    }

    void print_buffer()
    {
        for (const auto& i: buffer_) {
            if (i == 0) {
                std::cout << "NULL";
            } else {
                std::cout << i;
            }
            std::cout << " ";
        }
        std::cout << "\n";
    }

private:
    std::array<char_type, SIZE> buffer_;
};

int main()
{
    ArrayedStreamBuffer<10> streambuf;
    std::ostream stream(&streambuf);

    stream << "hello";
    stream << ",";

    streambuf.print_buffer();
}

Output: 

h e l l o , NULL NULL NULL NULL

See also

 repositions the beginning, next, and end pointers of the input sequence
(protected member function)
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