std::basic_streambuf<CharT,Traits>:: setp

Sets the values of the pointers defining the put area.

After the call, pbase ( ) == pbeg , pptr ( ) == pbeg and epptr ( ) == pend are all true .

If any of [ pbeg , pend ) is not a valid range , the behavior is undefined.

Parameters

Example

#include <array>
#include <cstddef>
#include <iostream>
 
// Buffer for std::ostream implemented by std::array
template<std::size_t size, class CharT = char>
struct ArrayedStreamBuffer : std::basic_streambuf<CharT>
{
    using Base = std::basic_streambuf<CharT>;
    using char_type = typename Base::char_type;
 
    ArrayedStreamBuffer()
    {
        // put area pointers to work with “buffer”
        Base::setp(buffer.data(), buffer.data() + size);
    }
 
    void print_buffer()
    {
        for (char_type i : buffer)
        {
            if (i == 0)
                std::cout << "\\0";
            else
                std::cout << i;
            std::cout << ' ';
        }
        std::cout << '\n';
    }
 
private:
    std::array<char_type, size> buffer{}; // value-initialize “buffer”
};
 
int main()
{
    ArrayedStreamBuffer<10> streambuf;
    std::ostream stream(&streambuf);
 
    stream << "hello";
    stream << ",";
 
    streambuf.print_buffer();
}

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Defect reports

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

See also