std::basic_ios<CharT,Traits>::setstate
 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.
Parameters
| state | - |  stream error state flags to set. It can be a combination of the following constants: 
  | 
Return value
(none).
Example
#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
See also
|  returns state flags  (public member function)  | 
|
|  modifies state flags  (public member function)  | 
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