std::basic_ios<CharT,Traits>::setstate
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std::basic_ios 
 
 
 
 
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basic_ios::setstate
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void setstate( iostate state );
 
 
Sets the stream error flags state in addition to currently set flags. Essentially calls clear(rdstate() | state). May throw an exception.
Contents
[edit] Parameters
 state
 -
 stream error state flags to set. It 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
[edit] Return value
(none)
[edit] Example
Run this code
#include <iostream> #include <sstream> int main() { std::ostringstream stream; if (!stream.fail()) std::cout << "stream is not fail\n"; stream.setstate(std::ios_base::failbit ); if (stream.fail()) std::cout << "now stream is fail\n"; if (!stream.good()) std::cout << "and stream is not good\n"; }
Output:
stream is not fail now stream is fail and stream is not good