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May 19, 2015 - A Look At The New Commandlinefu
I've put together a short writeup on what kind of newness you can expect from the next iteration of clfu. Check it out here.
March 2, 2015 - New Management
I'm Jon, I'll be maintaining and improving clfu. Thanks to David for building such a great resource!

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Psst. Open beta.

Wow, didn't really expect you to read this far down. The latest iteration of the site is in open beta. It's a gentle open beta-- not in prime-time just yet. It's being hosted over at UpGuard (link) and you are more than welcome to give it a shot. Couple things:

  • » The open beta is running a copy of the database that will not carry over to the final version. Don't post anything you don't mind losing.
  • » If you wish to use your user account, you will probably need to reset your password.
Your feedback is appreciated via the form on the beta page. Thanks! -Jon & CLFU Team

Rename .JPG to .jpg recursively

Terminal - Rename .JPG to .jpg recursively
find /path/to/images -name '*.JPG' -exec bash -c 'mv "$1" "${1/%.JPG/.jpg}"' -- {} \;
2010-01-07 15:41:17
User: sorpigal
Functions: bash find
Rename .JPG to .jpg recursively

Recursively rename .JPG to .jpg using standard find and mv. It's generally better to use a standard tool if doing so is not much more difficult.


There are 6 alternatives - vote for the best!

Terminal - Alternatives
find /path/to/images -name '*.JPG' -exec rename "s/.JPG/.jpg/g" \{\} \;
2010-01-02 19:12:37
User: renich
Functions: find rename
Tags: find rename

This command is useful for renaming a clipart, pic gallery or your photo collection. It will only change the big caps to small ones (on the extension).

Know a better way?

If you can do better, submit your command here.

What others think

find /path/to/images -name '*.jpg' -exec rename.ul .JPG .jpg {} +

rename.ul is the util-linux rename command, widely available on linux systems, possibly named just 'rename' if not overridden by perl rename (prename). Also here I use the + form of -exec instead of \; so that find will launch rename.ul on many file names at once, using many fewer process spawns. With -exec bash -c mv ... you launch a shell process which launches a mv process just to rename one file. It works, but for performance, you'd be much better off writing a shell script, which is a very standard tool.

Comment by bwoodacre 376 weeks ago

Thanks sorpigal.

This did exactly what I needed it to. I tried the other command but it failed. Maybe I had a typo.

@ bwoodacre. I should have totally used + instead of \; Dooh!

Comment by Xinerama 332 weeks and 4 days ago

Using the "-exec" option of "find" is not a good technique. Basically while it is running a command "find" is waiting, and not 'searching' for the next file.

This is why piping the output of "find" into "xargs" is a better idea. The filename gets cached by the pipeline ready for "xargs" to use when ready, while "find" continues to search.

See find -exec vs xargs


Also look at commands like "mv_perl" whcih can rename multiple files in the one command. You can have "xargs" feed lots of files to each command, or just one one command per directory.

Comment by anthony 332 weeks and 3 days ago

Your point of view

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