register a function to be called on exit
() function registers the given
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. At least 32
functions can always be registered, and more are allowed as long as sufficient
memory can be allocated.
If a shared object is unloaded from process memory using
, then any functions
registered by calling atexit
() from that shared
object will be called in reverse order and unregistered. Note that it is the
source of the call to atexit
() that matters, not
the source of the function that was registered.
() is very difficult to use correctly without
Unless absolutely necessary, please avoid using it.
() function returns the value 0 if
successful; otherwise the value -1 is returned and the global variable
is set to indicate the error.
- No memory was available to add the function to the list.
The existing list of functions is unmodified.
() function conforms to
The behavior when a shared object is unloaded is an extension to that