signal processes matching criteria
o Based on current NetBSD's pgrep(1) and pkill(1) with the following
differences:
1) -STABLE version does not support filtering by session
ID since this information is only available in kernel
space. -CURRENT supports this.
2) Added -M and -N flags following ps(1). Therefore, drop
additional privileges (drop_privs) if any of those flags
are defined.
3) kvm access without sgid
o Items (2) and (3) are based on jmallett code sent to me for
inspiration. :) Great thanks to jmallett for that.
Obtained from: NetBSD CVS (original pkill/pgrep code)
