std::basic_ios::rdstate

 

C++

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Technical Specifications

 

Input/output library

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C-style I/O

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basic_streambuf

basic_filebuf

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basic_stringstream

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istrstream (deprecated in C++98)

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basic_osyncstream (C++20)

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streamoff

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iostream_category (C++11)

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std::basic_ios

Member functions

basic_ios::basic_ios

basic_ios::~basic_ios

State functions

basic_ios::good

basic_ios::eof

basic_ios::fail

basic_ios::bad

basic_ios::operator!

basic_ios::operator bool

basic_ios::rdstate

basic_ios::setstate

basic_ios::clear

Formatting

basic_ios::copyfmt

basic_ios::fill

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basic_ios::exceptions

basic_ios::imbue

basic_ios::rdbuf

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basic_ios::widen

Protected member functions

basic_ios::init

basic_ios::move

basic_ios::swap

basic_ios::set_rdbuf

 

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)