Check whether two directories and their subdirectories are the same

Question

With diff -r I can do this task, however it takes so long because diff checks file's content.

I want something that determine that two files are the same regarding of their size, last modified, etc. But no checking bit by bit the file (for example a video takes sooo long)

Is there any other way?

Answer 1

Use the -q (--brief) option with diff -r (diff -qr). From the info page for GNU diff:

1.6 Summarizing Which Files Differ

When you only want to find out whether files are different, and you don't care what the differences are, you can use the summary output format. In this format, instead of showing the differences between the files, diff' simply reports whether files differ. The--brief' (`-q') option selects this output format.

This format is especially useful when comparing the contents of two directories. It is also much faster than doing the normal line by line comparisons, because `diff' can stop analyzing the files as soon as it knows that there are any differences.

This will not compare line by line, but rather the file as a whole, which greatly speeds up the processor (what' you're looking for).

Answer 2

Here's a quick python script that will check that the filenames, mtimes, and file sizes are all the same:

import os
import sys

def getStats(path):
    for pathname, dirnames, filenames in os.walk(path):
        for filename in ( os.path.join(pathname, x) for x in filenames ):
            stat = os.stat(filename)
            yield filename[len(path):], stat.st_mtime, stat.st_size

sys.exit(tuple(getStats(sys.argv[1])) != tuple(getStats(sys.argv[2])))

Answer 3

If you'd like to compare only a structure and some basic info about files, you can try something like this:

diff <(ls -laR $DIR1) <(ls -laR $DIR2)

I didn't test it, so any edits are welcome :)