std::basic_ios::rdstate

#include <iostream>
#include <sstream>
 
int main()
{
  std::ostringstream stream;
 
  if (stream.rdstate() == std::ios_base::goodbit) {
    std::cout << "stream state is goodbit\n";
  }
 
  stream.setstate(std::ios_base::eofbit);
 
  // check state is exactly eofbit (no failbit and no badbit)
  if (stream.rdstate() == std::ios_base::eofbit) {
    std::cout << "stream state is eofbit\n";
  }
}

stream state is goodbit
stream state is eofbit

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