std::basic_ios<CharT,Traits>::bad - cppreference.com

From cppreference.com

boolbad()const;Returns true if non-recoverable error has occurred on the associated stream. Specifically, returns true if

badbit

is set in rdstate().

See

ios_base::iostate

for the list of conditions that set badbit.

Parameters

(none)

Return value

true if a non-recoverable error has occurred, false otherwise.

Example

Run this code

#include<cstdlib>#include<fstream>#include<iostream>intmain(){std::ifstreamfile("test.txt");if(!file)// operator! is used here{std::cout<<"File opening failed\n";returnEXIT_FAILURE;}// typical C++ I/O loop uses the return value of the I/O function// as the loop controlling condition, operator bool() is used herefor(intn;file>>n;)std::cout<<n<<' ';std::cout<<'\n';if(file.bad())std::cout<<"I/O error while reading\n";elseif(file.eof())std::cout<<"End of file reached successfully\n";elseif(file.fail())std::cout<<"Non-integer data encountered\n";}See also

The following table shows the value of

basic_ios

accessors (

good()

,

fail()

, etc.) for all possible combinations of

ios_base::iostate

flags:

ios_base::iostate

flags basic_ios accessors eofbitfailbitbadbit

good()

fail()

bad()

eof()

operator bool

operator!

false false false true false false false true false false false true false true true false false true false true false false true false false false true false true true false true true false false true true false false false false false true true false true false true false true true true false true true true false false true false true false true true true true false true true true false true