update-test.sh

#!/bin/sh
TEST="$1"
PREFIX=tests
MATCH=0
while read name input output options
do
    [ _$name = _ ] && continue		# ignore empty lines
    [ _${name#\#} != _$name ] && continue	# ignore comment lines
    [ $name != "$TEST" ] && continue	# not the requested test
    [ _$output = _ ] && continue	# ignore incomplete lines
    MATCH=1
    ./tcpdump -n -t -r "$PREFIX/$input" $options >"$PREFIX/$output"
done < $PREFIX/TESTLIST
[ $MATCH = 0 ] && echo "test $TEST not found" >&2