std::basic_ios<CharT,Traits>::exceptions

 

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std::ios_base::iostate exceptions() const;	(1)
void exceptions( std::ios_base::iostate except );	(2)

Gets and sets the exception mask of the stream. The exception mask determines which error states trigger exceptions of type failure.

1) Returns the exception mask.

2) Sets the exception mask to except. If the stream has an error state covered by the exception mask when called, an exception is immediately triggered.

Parameters

except

-

exception mask

Return value

1) The current exception mask.

2) (none)

Example

Run this code

#include <fstream>
#include <iostream>
 
int main() 
{
    int ivalue;
    try
    {
        std::ifstream in("in.txt");
        in.exceptions(std::ifstream::failbit); // may throw
        in >> ivalue; // may throw
    }
    catch (const std::ios_base::failure& fail)
    {
        // handle exception here
        std::cout << fail.what() << '\n';
    }
}

Possible output:

basic_ios::clear: iostream error