< cpp‎ | utility‎ | program
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Defined in header <cstdlib>
int at_quick_exit( /*atexit-handler*/* func ) noexcept;
int at_quick_exit( /*c-atexit-handler*/* func ) noexcept;
(1) (since C++11)
extern "C++" using /*atexit-handler*/ = void();
extern "C" using /*c-atexit-handler*/ = void();
(2) (exposition only*)

Registers the function pointed to by func to be called on quick program termination (via std::quick_exit).

Calling the function from several threads does not induce a data race. The implementation is guaranteed to support the registration of at least 32 functions. The exact limit is implementation-defined.

The registered functions will not be called on normal program termination. If a function need to be called in that case, std::atexit must be used.


[edit] Parameters

func - pointer to a function to be called on quick program termination

[edit] Return value

0 if the registration succeeds, nonzero value otherwise.

[edit] Notes

The two overloads are distinct because the types of the parameter func are distinct (language linkage is part of its type).

[edit] Example

#include <cstdlib>
#include <iostream>
void f1()
    std::cout << "pushed first" << std::endl; // flush is intentional
extern "C" void f2()
    std::cout << "pushed second\n";
int main()
    auto f3 = []
        std::cout << "pushed third\n";


pushed third
pushed second
pushed first

[edit] See also

causes abnormal program termination (without cleaning up)
(function) [edit]
causes normal program termination with cleaning up
(function) [edit]
registers a function to be called on std::exit() invocation
(function) [edit]
causes quick program termination without completely cleaning up
(function) [edit]
C documentation for at_quick_exit