gcc extension - __attribute__ destructor

Giriş
 __attribute__ ((constructor)) ile main metodundan önce kod çalıştırmak

 __attribute__ ((destructor)) ile main metodundan sonra kod çalıştırmak mümkün.

Örnek
Şöyle yaparız.

#include<stdio.h>

/* Apply the constructor attribute to myStartupFun() so that it
    is executed before main() */
void myStartupFun (void) __attribute__ ((constructor));


/* Apply the destructor attribute to myCleanupFun() so that it
   is executed after main() */
void myCleanupFun (void) __attribute__ ((destructor));


/* implementation of myStartupFun */
void myStartupFun (void)
{
    printf ("startup code before main()\n");
}

/* implementation of myCleanupFun */
void myCleanupFun (void)
{
    printf ("cleanup code after main()\n");
}

int main (void)
{
    printf ("hello\n");
    return 0;
}

Örnek
Şöyle yaparız.

int main(void)
{
  ...;
}

__attribute__ ((destructor)) void after_main(void)
{
  ...
}