How do I change folder timestamps recursively?

Question

I was wondering if anyone knows how to change the timestamps of folders recursively based on the latest timestamp found of the files in that folder.

So for example:

jon@UbuntuPanther:/media/media/MP3s/Foo Fighters/(1997-05-20) The Colour and The Shape$ ls -alF
total 55220
drwxr-xr-x  2 jon jon    4096 2010-08-30 12:34 ./
drwxr-xr-x 11 jon jon    4096 2010-08-30 12:34 ../
-rw-r--r--  1 jon jon 1694044 2010-04-18 00:51 Foo Fighters - Doll.mp3
-rw-r--r--  1 jon jon 3151170 2010-04-18 00:51 Foo Fighters - Enough Space.mp3
-rw-r--r--  1 jon jon 5004289 2010-04-18 00:52 Foo Fighters - Everlong.mp3
-rw-r--r--  1 jon jon 5803125 2010-04-18 00:51 Foo Fighters - February Stars.mp3
-rw-r--r--  1 jon jon 4994903 2010-04-18 00:51 Foo Fighters - Hey, Johnny Park!.mp3
-rw-r--r--  1 jon jon 4649556 2010-04-18 00:52 Foo Fighters - Monkey Wrench.mp3
-rw-r--r--  1 jon jon 5216923 2010-04-18 00:51 Foo Fighters - My Hero.mp3
-rw-r--r--  1 jon jon 4294291 2010-04-18 00:52 Foo Fighters - My Poor Brain.mp3
-rw-r--r--  1 jon jon 6778011 2010-04-18 00:52 Foo Fighters - New Way Home.mp3
-rw-r--r--  1 jon jon 2956287 2010-04-18 00:51 Foo Fighters - See You.mp3
-rw-r--r--  1 jon jon 2730072 2010-04-18 00:51 Foo Fighters - Up in Arms.mp3
-rw-r--r--  1 jon jon 6086821 2010-04-18 00:51 Foo Fighters - Walking After You.mp3
-rw-r--r--  1 jon jon 3033660 2010-04-18 00:52 Foo Fighters - Wind Up.mp3

The folder "(1997-05-20) The Colour and The Shape" would have its timestamp set to 2010-04-18 00:52.

Thanks in advance!

Solution 1

Looks to me like you'll need to make a script (shell or Perl or whatever, but personally I'd use Perl) to parse the output of an ls -laF command and then invoke a touch command. In pseudo-code, that would look loosey like this:

while (`ls -laF $folder`)
{
  $tmp = echo $_ | awk '{print $6 $7}'
  if $tmp > $date { $date = $tmp}
}
touch $date $folder

Again, that is pseudo-code. Its meant to demonstrate the idea that I'm thinking of within 5 minutes. Do not expect the above to be similar to the code you end up producing.

Hope that helps.

Solution 2

Using TOUCH you can change the folder or file timestamp:

touch -t 1004180052 folder #(YYMMDDhhmm)

Options that you may want to know:

-r, --reference=FILE
    use this file's times instead of current time 
-t STAMP
    use [[CC]YY]MMDDhhmm[.ss] instead of current time 

With the -r you can specify a file to get teh timestamp from or you can use -t to set it yourself.

if you which to run it against all the files in the dir and using the last updated file update your folder ls would be a better alternative:

touch -r "`ls -1tA /path/to/folder | head -n 1`" /path/to/folder

Comments

[MonkeyWrench32]

Terribly sorry. I posted at the other one first and thought I'd get better luck here (turns out I was wrong). I will not do so in the future.