std::basic_ios<CharT,Traits>::rdstate

 

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std::basic_ios

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basic_ios::basic_ios

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State functions

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basic_ios::operator!

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basic_ios::rdstate

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iostate rdstate() const;

Returns the current stream error state.

Parameters

(none)

Return value

current stream error state. It is a bitmask type and can be a combination of the following constants:

Constant	Explanation
goodbit	no error
badbit	irrecoverable stream error
failbit	input/output operation failed (formatting or extraction error)
eofbit	associated input sequence has reached end-of-file

Example

Run this code

#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";
  }
}

Output:

stream state is goodbit
stream state is eofbit

See also

setstate	sets state flags (public member function)
clear	modifies state flags (public member function)