at_quick_exit

From cppreference.com
< c‎ | program
Defined in header <stdlib.h>
int at_quick_exit( void (*func)(void) );
(since C11)

Registers the function pointed to by func to be called on quick program termination (via 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, 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.

Example

#include <stdlib.h>
#include <stdio.h>
 
void f1(void)
{
    puts("pushed first");
    fflush(stdout);
}
 
void f2(void)
{
    puts("pushed second");
}
 
int main(void)
{
    at_quick_exit(f1);
    at_quick_exit(f2);
    quick_exit(0);
}

Output:

pushed second
pushed first

References

  • C17 standard (ISO/IEC 9899:2018):
  • 7.22.4.3 The at_quick_exit function (p: 255)
  • C11 standard (ISO/IEC 9899:2011):
  • 7.22.4.3 The at_quick_exit function (p: 351)

See also

causes abnormal program termination (without cleaning up)
(function)
causes normal program termination with cleaning up
(function)
registers a function to be called on exit() invocation
(function)
causes normal program termination without completely cleaning up
(function)