1) Missing include.
2) Constness.
3) ANSIfication.
4) Avoid some shadowing.
5) Add/clarify some error messages.
6) Some int functions were using return without a value.
7) Mark some parameters as unused.
8) Cast a value we know is non-negative to a size_t before comparing.
depend on namespace pollution in <signal.h>. (truss shouldn't be
using timevals anyway, since it was implemented long after timevals
were obsoleted by timespecs.)
some header files (e.g., <err.h>) include <machine/something.h>, and this
will not pick up the right header files, so it may be removed eventually
anyway. But some people who are not willing to build the right way
apparantly want this, so this is for them.
Correct usage: one of {-p pid, command} is required.
Open output file when command line is fully analyzed: incorrect `truss -o f'
command does not create an empty file anymore.