std::exception::what
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virtual const char* what() const throw();
(until C++11)
virtual const char* what() const noexcept;
(since C++11) (constexpr since C++26)
Returns the explanatory string.
[edit] Parameters
(none)
[edit] Return value
Pointer to a null-terminated string with explanatory information. The pointer is guaranteed to be valid at least until the exception object from which it is obtained is destroyed, or until a non-const member function on the exception object is called.
The returned string is encoded with the ordinary literal encoding during constant evaluation.
(since C++26)[edit] Defect reports
The following behavior-changing defect reports were applied retroactively to previously published C++ standards.
| DR | Applied to | Behavior as published | Correct behavior |
|---|---|---|---|
| LWG 108 | C++98 | it was unspecified when the returned pointer becomes invalid | specified |