std::system_error::what
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 < cpp | error | system error 
 
 
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std::system_error 
 
 Member functions
system_error::what
virtual const char* what() const noexcept;
 
 (since C++11) 
Returns the explanatory string.
[edit] Parameters
(none)
[edit] Return value
Pointer to a null-terminated string with explanatory information.