Unhandled C++ exceptions
If a matching handler (or ellipsis catch
handler) cannot be found for the current exception, the predefined terminate
run-time function is called. (You can also explicitly call terminate
in any of your handlers.) The default action of terminate
is to call abort
. If you want terminate
to call some other function in your program before exiting the application, call the set_terminate
function with the name of the function to be called as its single argument. You can call set_terminate
at any point in your program. The terminate
routine always calls the last function given as an argument to set_terminate
.
Example
The following example throws a char *
exception, but does not contain a handler designated to catch exceptions of type char *
. The call to set_terminate
instructs terminate
to call term_func
.
// exceptions_Unhandled_Exceptions.cpp
// compile with: /EHsc
#include <iostream>
using namespace std;
void term_func() {
cout << "term_func was called by terminate." << endl;
exit( -1 );
}
int main() {
try
{
set_terminate( term_func );
throw "Out of memory!"; // No catch handler for this exception
}
catch( int )
{
cout << "Integer exception raised." << endl;
}
return 0;
}
Output
term_func was called by terminate.
The term_func
function should terminate the program or current thread, ideally by calling exit
. If it doesn't, and instead returns to its caller, abort
is called.