function chk
{
    URL=$1
    TMP=$(mktemp)
    TMP2=$(mktemp)
    TMP3=$(mktemp)
    WEB_UPDATES="$HOME/web_updates"

    if [ ! -d $WEB_UPDATES ];
    then
        mkdir $WEB_UPDATES
	cd $WEB_UPDATES
        git init
        cd ..
    fi

    PAGE_R=$( echo $URL | sed s/'\/'/_/g | sed s/'\:'/_/g | sed s/'\?'/_/g )
    PAGE_NEW="$WEB_UPDATES/$PAGE_R.new"
    PAGE_OLD="$WEB_UPDATES/$PAGE_R.old"
    PAGE_DIFF="$WEB_UPDATES/$PAGE_R.diff"

    rm -f $PAGE_NEW

    lynx -useragent=asd $URL -dump -nolist -error_file=$TMP > $TMP2 2> $TMP3

    if [ ! -e $TMP ]; then return; fi
   
    cat $TMP3 | grep -v "User-Agent string does not"
 
    if grep --quiet 200 $TMP; then
        true
    else
        rm -f $TMP $TMP2 $TMP3
        return
    fi
   
    cat $TMP2 | grep "$2" > $PAGE_NEW

    if [ -e "$PAGE_NEW" ];
    then
        if [ -e "$PAGE_OLD" -a -e "$PAGE_NEW" ]; 
        then
            diff --old-line-format='(removed) %L' --new-line-format='(added) %L' --unchanged-line-format='' "$PAGE_OLD" "$PAGE_NEW" >"$PAGE_DIFF" 
            if [ -s "$PAGE_DIFF" ]; 
            then
                echo web_updates_fn.sh: $URL changed
                cat "$PAGE_DIFF"
            fi
        fi 
        mv "$PAGE_NEW" "$PAGE_OLD" 
        rm -f "$PAGE_DIFF"
    fi

    rm -f $TMP $TMP2 $TMP3
}