Question

Is there any difference between

   int on_exit(void (*function)(int , void *), void *arg); 

and

   int atexit(void (*function)(void)); 

other than the fact that the function used by on_exit gets the exit status?

That is, if I don’t care about the exit status, is there any reason to use one or the other?

Edit: Many of the answers warned against on_exit because it’s non-standard. If I’m developing an app that is for internal corporate use and guaranteed to run on specific configurations, should I worry about this?

Answer 1

According to this link I found, it seems there are a few differences. on_exit will let you pass in an argument that is passed in to the on_exit function when it is called… which might let you set up some pointers to do some cleanup work on when it is time to exit.

Furthermore, it appears that on_exit was a SunOS specific function that may not be compatible on all platforms… so you may want to stick with atexit, despite it being more restrictive.