NAME¶

std::at_quick_exit - std::at_quick_exit

Synopsis¶

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

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.

Parameters¶

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

Return value¶

0 if the registration succeeds, nonzero value otherwise.

Notes¶

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

Example¶

// Run this code

#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";
};

std::at_quick_exit(f1);
std::at_quick_exit(f2);
std::at_quick_exit(f3);
std::quick_exit(0);
}

Output:¶

pushed third
pushed second
pushed first

See also¶

abort causes abnormal program termination (without cleaning up)
(function)
exit causes normal program termination with cleaning up
(function)
atexit registers a function to be called on std::exit() invocation
(function)
quick_exit causes quick program termination without completely cleaning up
(C++11) (function)
C documentation for
at_quick_exit