The
atexit()
function
registers the given
function
to be called at program exit, whether via
exit(3)
or via return from the program's
main().
Functions so registered are called in reverse order;
no arguments are passed.
These functions must not call
exit();
if it should be necessary to terminate the process while in such a
function, the
_exit(2)
function should be used.
(Alternatively, the function may cause abnormal
process termination, for example by calling
abort(3).)
At least 32 functions can always be registered,
and more are allowed as long as sufficient memory can be allocated.
The
atexit_b()
function behaves identically to
atexit(),
except that it takes a block, rather than a function pointer.
