std::basic_streambuf::setp - std::basic_streambuf::setp
protected:
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
pbeg - pointer to the new beginning of the put area
pend - pointer to the new end of the put area
// 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 << "\\0";
} 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();
}
setg repositions the beginning, next, and end pointers of the
input sequence
(protected member function)