number files in directory according to their modification time

IFS=$'\n'; i=1; ls -lt *mp3 | cut -d ":" -f2 | cut -d " " -f2- | while read f; do mv "$f" $(echo "$i"."$f"); ((i++)); done
i use this after ripping internet radio streams to number the files as they originally played (even though streamripper can do this with -q). to number other types of files, or all files, just change the *mp3. to rename directories only you could use ... ls -lt | grep ^d | cut -d ":" -f2 | cut -d " " -f2- | while read ...
Sample Output
$> touch a.mp3 b.mp3 c.mp3 d.mp3
$> ls
a.mp3  b.mp3  c.mp3  d.mp3

$> IFS=$'\n'; i=1; ls -lt *mp3 | cut -d ":" -f2 | cut -d " " -f2- | while read f; do mv "$f" $(echo "$i"."$f"); ((i++)); done

$> ls
1.a.mp3  2.b.mp3  3.c.mp3  4.d.mp3

By: m1cawber
2011-01-22 00:21:12

What Others Think

Parsing ''ls'' output is a bad idea (, therefore by using globs instead you can avoid using the IFS variable and the ''cut'' command. Try using globs ;)
RanyAlbeg · 573 weeks ago
For most people's usage, you can simplify your command. Get rid of the -l and replace it with -1 (dash one) to put each filename on a separate line. i=1; ls -1t *mp3 | while read f; do mv "$f" $(echo "$i"."$f"); ((i++)); done
flatcap · 572 weeks and 6 days ago
RanyAlbeg thanks for the link, good information there. and flatcap thx for cutting cut =p. ls -1 is new to me.
m1cawber · 572 weeks and 6 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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