Detecting broken links

check.sh

#!/bin/sh
while getopts v OPTION ; 
do
    case "$OPTION" in
        v) VERBOSE=true ; shift ;;
    esac
done

urls=$(grep -i -E -o 'https?://[^ )]*[^), ]' $1)

# HEAD may be better for performance but sometimes does not work.
method="GET"

for url in $urls
do

test $VERBOSE && echo test: $url
status_line=`curl -s -I -X $method $url | head -n1`
result1=$?
test $VERBOSE && echo status: $status_line
echo $status_line | grep '^\S* [23][0-9][0-9]' > /dev/null
result2=$?

[ $result1 -ne 0 -o $result2 -ne 0 ] && echo $url

done