bash - finding duplicities using md5sum (for NTI / OSU-P, Ing. Jana Kolaja Ehlerová, Ph.D.)

mydiff.sh

#!/bin/bash

# the same contents file list 
# finding using md5sum 

#echo $1
if [ "$1" = "--help" ]; then
    echo "here will be some help..."
    echo "using: "
    echo "mydiff [directory]"
else
    if [ "$1" = "" ]; then
        ADR="."
    else
        # echo "explicit input processing..."
        ADR=$1
    fi
    #echo $ADR
    #ls $ADR
    # temporary directory creating
    TEMP=$( mktemp -d )
    # insert file name into list according to its hash
    # for each hash one file 
    find $ADR -type f | 
        while read f; do
            HASH=$(md5sum $f | cut -f1 -d' ' ) 
            NAME=$(md5sum $f | cut -f3 -d' ' ) 
            echo $NAME >> $TEMP/$HASH
        done
    # file lists processing
    for i in $(find $TEMP -type f); do 
        DUPL=$(cat $i | wc -l)
        if (( $DUPL > 1 )); then
            echo -n "hash: "$(echo $i | cut -d"/" -f4)" - "
            echo $DUPL" files with equivalent content"
            cat $i
        fi
    done
    # temporary directory removing
    rm -rf $TEMP
fi