Shell Programming and Scripting

f1.log - There is a difference in the f1 and f2, please find the below difference:
......
f2.log - No difference found
f3.log - No difference found
Additional.log - There is additional file in D2 with filename as f4

diff -rs a b |
	awk -F"[: \t]" '
	/^diff/ { print "difference between " $3, $4 ; getline ; getline
	while(/^[<>-]/) { print ; if(getline != 1) break } }
	/^Only in/ { print "There is additional file in "$3" with filename as "$NF } 
	/identical$/ { N=split($2, A, "/"); print A[N] " - no difference found" }' >$3.log

log0=/tmp/changes.log

diff -r <(ls -1 $1 | sort)  <(ls -1 $2 | sort) > /tmp/junk0

if [ ! -z /tmp/junk0 ]; then
    >$log0
    printf "Dirs %s and %s differ\n" $1 $2 > $log0
    echo "~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~" >> $log0

    while read buf
    do
        if [[ ${buf:0:1} == '<' ]]; then
            printf "%s.log: File added: %s\n" $1 ${buf##*<} >> $log0
        elif [[ ${buf:0:1} == '>' ]]; then
            printf "%s.log: File added: %s\n" $2 ${buf##*>} >> $log0
        fi
    done < /tmp/junk0
fi

cat $log0
# rm  /tmp/junk0 $log0