Rename batch of specific files using bash

Question

Say I have a folder which contains files like this: a constant prefix and then an underscore and some description which is different for every file:

constantnamehere_description1.doc
constantnamehere_description2.doc
.
.
etc

Here description1, description2 etc just symbolized the different descriptions and not the actual number 1,2 etc..

How can I rename these files to just this?

constantnamehere1.doc
constantnamehere2.doc
.
.
etc

Here the numbers 1,2,..,etc symbolize the actual sequential ending that i want my files to have after the renaming. The sequential ending (1,2,3,...,end) is very important.

Till now I have tried:

for i in *.doc; do mv "$i" "{i/_*.doc/ .doc}"; done

example actual file names

1003407_cc_1.vtk
1003407_cc_2.vtk
1003407_cc_3.vtk
1003407_cv.left.right.vtk
1003407_thalamo_frontal.left.vtk

I want to be like:

1003407_1.vtk
1003407_2.vtk
1003407_3.vtk
1003407_4.vtk
1003407_5.vtk

To make it extremely clear: I want everything to be removed after the first underscore and to be replaced with sequential numbers keeping the ".vtk" extension of the file

But your question states that there is no such order at the beginning because the numbers are actually just placeholders for different desriptions. So how can it remain unchanged? :) I meant, does it matter which file is number 1, number 2 and so on? — Michael Jaros, Mar 04 '15 at 15:27
The way you put it no. I just meant that i want the operation every time to give the same "random" result concerning the numbering. Because i will perform it to a lot of folders which contain the same files, so after the operation, i want the correspondence to still apply — azal, Mar 04 '15 at 15:32
Ok, in that case you should be fine with my solution posted below because Bash will replace the `*` "with an alphabetically sorted list of file names matching the pattern" (from `bash(1)`). — Michael Jaros, Mar 04 '15 at 15:36

score 1 · Answer 1 · edited May 23 '17 at 11:43

1

Using the an answer to Capturing Groups From a Grep RegEx, we can generate a regex for these file names and then rename by using the captured groups:

$ regex="([^_]*)_[^0-9]*([0-9]*).([a-z]*)"
$ for f in *doc
do 
    [[ $f =~ $regex ]]
    echo "mv $f --> ${BASH_REMATCH[1]}${BASH_REMATCH[2]}.${BASH_REMATCH[3]}"
done

The regex says: get everything up to _, then expect some characters until a digit is found. Catch that set of digits and then expect a dot followed by the extension.

edited May 23 '17 at 11:43

Community

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answered Mar 04 '15 at 15:11

fedorqui

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i'll give it a try and i ll get back at you – azal Mar 04 '15 at 15:14
it works fine but it doesn't put the number 1,2,3 etc at the end of constantnamehere – azal Mar 04 '15 at 15:18
@gelazari You are right, I didn't notice this before. Just completely rewrote the answer. – fedorqui Mar 04 '15 at 15:31
check now my edit at the bottom with actual file names – azal Mar 04 '15 at 15:40
1

@gelazari So now, after all the attempts we've been doing, you come up with some different approach: apparently, your input files do not have a number in there, whereas you did state that in the initial question. Make your mind clear and indicate what you want, because I am not going to update my answer anytime you come up with a different idea. – fedorqui Mar 04 '15 at 15:47
some of them do have a number at the end but some don't. Thats why i posted actual names. – azal Mar 04 '15 at 15:48
@gelazari You should have said that beforehand. It is tiring to keep updating the answer and I am not going to do it anymore. – fedorqui Mar 04 '15 at 15:52
1

In simple terms I want everything to be removed after the first underscore and to be replaced with sequential numbers keeping the ".vtk" extension of the file – azal Mar 04 '15 at 15:52
@gelazari check the first version of the answer: http://stackoverflow.com/revisions/28857893/1 It should be trivial to get your desired output from that version, you just need to add the counter. – fedorqui Mar 04 '15 at 15:58
@MichaelJaros i voted you up guys but i solved it with my way. thank you – azal Mar 04 '15 at 16:18

Michael Jaros · Answer 2 · 2015-03-04T15:56:08.307

1

Use rename:

i=1
for file in *_*.vtk
do 
  rename "s/_[^.]*/${i}/" "$file"
  i=$(( i + 1 ))
done

This removes everything between the underscore and the first . from all files matching the *_*.vtk pattern. If your filenames contain more than one ., the pattern needs to be adapted.

EDIT: Solution modified according to modified question.

edited Mar 04 '15 at 15:56

answered Mar 04 '15 at 15:12

Michael Jaros

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how can it be modified to add also 1,2,3,etc at the end of the name? – azal Mar 04 '15 at 15:29
I've just added the numbering. Now I have used some Bash too in addition to `rename`. It's still not too complex. – Michael Jaros Mar 04 '15 at 15:33
It looks quite risky to add the numbers sequentially, not very sure if this matches the OP requests – fedorqui Mar 04 '15 at 15:34
check now my edit at the bottom with actual file names – azal Mar 04 '15 at 15:40
@gelazari: Is it important to preserve the number in the variable part of the filename if there is any? – Michael Jaros Mar 04 '15 at 15:45
@fedorqui: I may have assumed too much, but if I read the comments on the question, this looks like what the OP wants to me. Maybe after my last question we will know. – Michael Jaros Mar 04 '15 at 15:47
no. I just want them to have sequential numbers after the constantPrefix but of course, if i perform the same operation in different folders containing the same set of files, i want them to rename all the files exactly with the same way every time. – azal Mar 04 '15 at 15:47
Ok, then the sequential numbering in my code should meet your requirements. Bash performs wildcard (e.g. `*`) expansion alphabetically, so the result should be always the same with the same set of files. – Michael Jaros Mar 04 '15 at 15:49
@MichaelJaros is there any different way using mv instead of rename? I want to perform the operation also on a macintosh – azal Mar 04 '15 at 15:53
1

@gelazari: Sure there is, but it needs a different approach and I wish you had given me this little information before letting me modify the `rename` approach 10 times :( Unfortunately I have to attend to something else now, but I'm sure some of the other members can help. I'll suggest to retag for Mac, maybe that helps. – Michael Jaros Mar 04 '15 at 16:02

score 1 · Accepted Answer · answered Mar 04 '15 at 16:13

1

I solved it like this:

i=0; 
for file in *.vtk; do mv "${file}" 100307_"${i}".vtk; i=$((i+1)); done

answered Mar 04 '15 at 16:13

azal

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Rename batch of specific files using bash

3 Answers3