std::basic_ios::setstate
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                    |   void setstate( iostate state ); 
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Sets the stream error flags state in addition to currently set flags. Essentially calls clear(rdstate() | state). May throw an exception.
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[edit] Parameters
| state | - |   stream error state flags to set. It can be a combination of the following constants:
 
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[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
[edit] See also
|    returns state flags  (public member function)  | 
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|    clears error and eof flags  (public member function)  |