Bulk Rename

[swestrup]

Am I right that there isn't a half-decent bulk rename command out there for Linux?  I did a search and found a bunch, but they all rely on regex which is not terribly useful when what you want to do is pull a number out of the middle of a file name, do math on it, and depending on the result replace it with a string containing a different embedded number.

(Okay, maybe this can be done with Perls ultra-extended regular expressions, but after rereading how they work a dozen times, and trying 30 different patterns, I gave up as the documentation is inadequate and I haven't been able to figure out how to express this.)

This, by-the-way is what you want to do if you have 1000 files numbered sequentially, from 10 years of a TV show, and you want to rename them as season and episode numbers, and the number of episodes per season was not a constant...

Okay, I know this is an edge case, but if I were to write a bulk rename, this would be one of the things I would, for certain, want to make easy.  Anything less complex and you can just throw together a one-line bash for-loop to handle it.

Comments

[swestrup]

> Or am I missing something?

Just that its on the border between what the command line stuff will handle easily, and what you need to write a script for.

Frankly, its annoying to have to write a script because I have to figure out how to use a few dozen commands and weave them together. Same with bash.

In the end I broke the problem into pieces by first moving each group into its own subdir and then running slightly-modified 1-line commands on each subdir. But frankly, when I write a for loop that passes something in turn through echo, cut, tr, and xargs 'mv', I start thinking there has to be a better way...

(see, I need to process the files in numerical sort order, despite there being a variable number of digits in the numbers...)

[sps.livejournal.com]

perl -e 'for (sort {$a<=>$b} <*>) /\(\d+\)\.sthg/ and rename $_, (100+$1).".sthgelse"' ishly?

[swestrup]

I hate perl -e because it causes me to have to worry about at least two levels of different escapes at the same time. As a result it takes me forever to get anything that works.

[joenotcharles.livejournal.com]

Why the fetish for doing everything on one line? Put your script in a text file, run the text file, fix mistakes, delete the text file when you're done, or save it somewhere if you think it'll be useful again.

If it's complicated enough that it takes you significant brain power to figure out how to shove it into a one-liner, or to work out the escaping involved, then the extra time taken to write to and delete a text file goes toward saving you from that, and it makes debugging the inevitable mistakes so much easier.

[skjalm.livejournal.com]

Agreed! Doing one liners (in whatever language) is fun, but sometimes it's not worth the extra hassle if the point of the exercise is to get something done rather than to do a nifty one liner ;)

That being said I couldn't help myself (see comment below) ;)

[swestrup]

Your mileage may vary, of course, but I find it MUCH faster to just shove everything onto one line, and have the final generated command echoed rather than run. No edit, save, try cycle. I just move the cursor to the middle of the line, change something and hit RETURN to try it out.