In new BSDs changes to argv[] do not show up in ps(1) output,

In new BSDs changes to argv[] do not show up in ps(1) output,
instead one must use setproctitle().  This was already addressed
by change #6457, but the below has a new variant for FreeBSD 4.0
or later, and the matter is also documented more.
Subject: [ID 20000801.007] setting $0 on FreeBSD 4.x does not get reflected in /bin/ps
Message-Id: <20000801154139.A53740@yahoo-inc.com>

p4raw-link: @6457 on //depot/perl: 0c9177abdae6e91f4dfdab2ef3cc817ec901e51eon //depot/metaconfig: efc5abcdbec468dfb20e18acbe3ab6c1cd9e92c3

p4raw-id: //depot/perl@6483