orphans: a q&d shell script to look for orphan functions in my code

orphans.sh

#! /bin/sh
#
# Find functions that are defined but not referenced in a body of C code

test -f tags || ctags -M *.c

test -f tags || exit 1

FILES=`awk -F'	' '{print $2}' < tags | sort |uniq`

trap "rm -f functions called" 0 1 2 3 5 9

rm -f functions called intermediate

awk -F'	' '{print $1}' < tags > functions

(   echo main
    for x in $FILES "$@"; do
	sed -e 's/(/(@ /g' $x | \
	tr '@' '\n' | \
	sed -n \
	    -e 's/^.*[^a-zA-Z0-9_]\([a-zA-Z_][a-zA-Z0-9_]*\)(.*/\1/p'
    done ) | sort | uniq | fgrep -f functions > called

fgrep -v -f called functions