atexit - register a function to run at process termination
or object unloading
int atexit(void (*func)(void));
The atexit() function registers the function pointed to by
func to be called without arguments on normal termination of
the program or when the object defining the function is
Normal termination occurs by either a call to the exit(3C)
function or a return from main(). Object unloading occurs
when a call to dlclose(3DL) results in the object becoming
The number of functions that may be registered with atexit()
is limited only by available memory (refer to the
_SC_ATEXIT_MAX argument of sysconf(3C)).
After a successful call to any of the exec(2) functions, any
functions previously registered by atexit() are no longer
On process exit, functions are called in the reverse order
of their registration. On object unloading, any functions
belonging to an unloadable object are called in the reverse
order of their registration.
Upon successful completion, the atexit() function returns 0.
Otherwise, it returns a non-zero value.
The atexit() function may fail if:
Insufficient storage space is available.
The functions registered by a call to atexit() must return
to ensure that all registered functions are called.
There is no way for an application to tell how many func-
tions have already been registered with atexit().
See attributes(5) for descriptions of the following attri-
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
| Interface Stability | Standard |
| MT-Level | Safe |
exec(2), dlclose(3DL), exit(3C), sysconf(3C), attributes(5)
Man(1) output converted with