Created attachment 15196 [details] [review]
Include header with prototypes for signals.c, and change prototypes and
definitions to match. This should not have any side effects as function
arguments are ignored.
Ansify some functions with K&R definitions.
printhex.c:fprintfhex() could be changed to a "sane" implementation, but
only change was "ansification".
Applied as e06eddafd5f72f6f0782e37e9617c2e874021038