cleanup_register() uses its argument in contradictory ways

[Terrence Enger]

Greetings,

I notice that cleanup_register() in src/exithandle.c calls
both signals_register() and atexit() with its argument.  But
signals_register() takes in effect void(*)(void), while
atexit() takes void(*)(void).  I wonder how you can use one
function in both calls.  Can anybody here help me
understand?

FWIW, the functions passed to cleanup_register() are
  SYSTEM_CLEANUP
  server_cleanup
  Lock_Cleanup
  rcs_cleanup
The three of these take a void argument lists, and I wrote a
SYSTEM_CLEANUP like that, too.

Thank you, all, for your attention.

Terry.
Available for contract programming.