Rename more than one directory at once

Question

I have bunch of directories such as

2013_03_12_18_26_am
2013_03_12_18_26_cu
2013_03_12_18_26_ig
2013_03_12_18_26_mdf
2013_03_12_18_26_pih
2013_03_12_18_26_tn
2013_03_12_18_26_an
2013_03_12_18_26_cv
2013_03_12_18_26_ik
2013_03_12_18_26_mhr
2013_03_12_18_26_pnb    
2013_03_12_18_26_to

What I want to do is rename them to their last two characters, example: 2013_03_12_18_26_am to am, I know I can do this one by one mv 2013_03_12_18_26_am am but that would take a long time. Can this be accomplis from the shell script?

I want everything after the last "_" to be the name of the new directory.

Answer 1

I like the rename command for this, which allows perl regexp like so:

rename 's/.*([a-z]{2})$/$1/' *

Answer 2

I noticed that those dir-names have no spaces, or other special chars. so you could try:

ls|xargs -n1 |sed -r 's/(.*_)(.*)/mv & \2/'

to print mv cmd for you. if you think all commands are correct, then you just pipe it to |sh

note, ls part you could change to get only those dirs.

Answer 3

This assume all (and only all) of your folders are in one directory. So be careful...

Original:

marks-mac-pro:test mstanislav$ ls
2013_03_12_18_26_am 2013_03_12_18_26_an 2013_03_12_18_26_cu 2013_03_12_18_26_cv     2013_03_12_18_26_ig 2013_03_12_18_26_ik 2013_03_12_18_26_mdf    2013_03_12_18_26_mhr    2013_03_12_18_26_pih    2013_03_12_18_26_pnb    2013_03_12_18_26_tn 2013_03_12_18_26_to

Shell Script:

marks-mac-pro:test mstanislav$ for i in `ls .`; do NEW=`echo $i | cut -d_ -f6`; mv $i $NEW; done

Result:

marks-mac-pro:test mstanislav$ ls
am  an  cu  cv  ig  ik  mdf mhr pih pnb tn  to

Please test this before doing it on the real data, just to make sure. Again, only do this in a directory with JUST the folders you want to rename, or re-write the first part for the ls to be more specific.

Answer 4

 for d in *_??
 do
     newd=$(expr $d : '.*_\([a-z][a-z]*\)')
     mv $d $newd
 done

Answer 5

If all directories following the above form then in bash you can use the following variable subsitituion to extract the characters after the final _

var=2013_03_12_18_26_am
echo ${var##*_} #am

You can then rename all directories in the folder with:

for dir in *_*; do #as there may be more than 2 chars after final _
    new_dir=${dir##*_}
    mv $dir $new_dir
done

Of course you will want to add checks to make sure you are only moving directories and that you aren't overwriting anything.