on_exit - register a function to be called at normal process termination
#include <stdlib.h>
int on_exit(void (*function)(int , void *), void *arg);Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
The on_exit() function registers the given function to be called at normal process termination, whether via exit(3) or via return from the program's main(). The function is passed the status argument given to the last call to exit(3) and the arg argument from on_exit().
The same function may be registered multiple times: it is called once for each registration.
When a child process is created via fork(2), it inherits copies of its parent's registrations. Upon a successful call to one of the exec(3) functions, all registrations are removed.
The on_exit() function returns the value 0 if successful; otherwise it returns a nonzero value.