Compare all file sizes of 2 directories in bash

Sometimes it happens that for some reason the process of copying many files (i.e. to ext开发者_运维技巧ernal HDD; using Nautilus file manager) crashes. If I then start it again, I use to ignore already existing files, though some of them were not copied 100%. So the properties window shows me "460 Files (225 GB)" in source folder and "460 Files (222 GB)" in destination folder...

How do I now find out which files have only been copied partially (maybe using ls and diff)?

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If you have rsync available, that works just fine between two local directories.

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for f1 in dir1/*
do
    f2="dir2/${f##*/}"
    if [[ $(sum "$f1") != $(sum "$f2") ]]
    then
        printf 'File %s does not match %s\n' "$f1" "$f2"
    fi
done

Or you could use this as your test:

    if ! diff -q "$f1" $f2" >/dev/null

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i modified dennis' code. it compares file sizes. Faster but not safer then comparing checksums..

source=/???
target=/???


for i in "$source"/*
do
 f1=`stat -c%s $i`
 f2=`stat -c%s $target/${i##*/}`
  if [ "$f1" = "$f2" ]; then
        echo "$i" "$f1" VS "$target/${i##*/}" "$f2" "====>>>" "OK"
  else
        echo "$i" "$f1" VS "$target/${i##*/}" "$f2" "====>>>" "BAD"
  fi
done