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Returns
This is equivalent to calling member fail.
Concurrent access to the same stream object may cause data races.
Reference
C library:
- <cassert> (assert.h)
- <cctype> (ctype.h)
- <cerrno> (errno.h)
-
<cfenv> (fenv.h)C++11
- <cfloat> (float.h)
-
<cinttypes> (inttypes.h)C++11
- <ciso646> (iso646.h)
- <climits> (limits.h)
- <clocale> (locale.h)
- <cmath> (math.h)
- <csetjmp> (setjmp.h)
- <csignal> (signal.h)
- <cstdarg> (stdarg.h)
-
<cstdbool> (stdbool.h)C++11
- <cstddef> (stddef.h)
-
<cstdint> (stdint.h)C++11
- <cstdio> (stdio.h)
- <cstdlib> (stdlib.h)
- <cstring> (string.h)
-
<ctgmath> (tgmath.h)C++11
- <ctime> (time.h)
-
<cuchar> (uchar.h)C++11
- <cwchar> (wchar.h)
- <cwctype> (wctype.h)
Containers:
-
<array>C++11
- <deque>
-
<forward_list>C++11
- <list>
- <map>
- <queue>
- <set>
- <stack>
-
<unordered_map>C++11
-
<unordered_set>C++11
- <vector>
-
Input/Output:
Multi-threading:
-
<atomic>C++11
-
<condition_variable>C++11
-
<future>C++11
-
<mutex>C++11
-
<thread>C++11
-
Other:
- <algorithm>
- <bitset>
-
<chrono>C++11
-
<codecvt>C++11
- <complex>
- <exception>
- <functional>
-
<initializer_list>C++11
- <iterator>
- <limits>
- <locale>
- <memory>
- <new>
- <numeric>
-
<random>C++11
-
<ratio>C++11
-
<regex>C++11
- <stdexcept>
- <string>
-
<system_error>C++11
-
<tuple>C++11
-
<type_traits>C++11
-
<typeindex>C++11
- <typeinfo>
- <utility>
- <valarray>
<ios>
types
manipulators
other functions
-
iostream_categoryC++11
-
basic_ios
- basic_ios::~basic_ios
- basic_ios::basic_ios
public members
- basic_ios::bad
- basic_ios::clear
- basic_ios::copyfmt
- basic_ios::eof
- basic_ios::exceptions
- basic_ios::fail
- basic_ios::fill
- basic_ios::good
- basic_ios::imbue
- basic_ios::narrow
- basic_ios::operator bool
- basic_ios::operator!
- basic_ios::rdbuf
- basic_ios::rdstate
- basic_ios::setstate
- basic_ios::tie
- basic_ios::widen
protected members
- basic_ios::init
-
basic_ios::moveC++11
-
basic_ios::set_rdbufC++11
-
basic_ios::swapC++11
public member function
<ios> <iostream>
std::basic_ios::operator!
bool operator!() const;
Evaluate stream (not)
true if no error flag is set (either failbit or badbit), and false otherwise.This is equivalent to calling member fail.
Parameters
noneReturn Value
true if either failbit or badbit is set.false otherwise. Example
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Data races
Accesses the stream object.Concurrent access to the same stream object may cause data races.
Exception safety
Strong guarantee: if an exception is thrown, there are no changes in the stream.See also
- basic_ios::fail
- Check whether failbit or badbit is set (public member function)
- basic_ios::good
- Check whether state of stream is good (public member function)
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Spotted an error? contact us