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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

Recursive cat - concatenate files (filtered by extension) across multiple subdirectories into one file

Terminal - Recursive cat - concatenate files (filtered by extension) across multiple subdirectories into one file
find . -type f -name *.ext -exec cat {} > file.txt \;
2009-06-17 11:33:14
User: realgt
Functions: cat find
Recursive cat - concatenate files (filtered by extension) across multiple subdirectories into one file

Useful if you have to put together multiple files into one and they are scattered across subdirectories. For example: You need to combine all .sql files into one .sql file that would be sent to DBAs as a batch script.

You do get a warning if you create a file by the same extension as the ones your searching for.

find . -type f -name *.sql -exec cat {} > BatchFile.txt \;


There are 3 alternatives - vote for the best!

Terminal - Alternatives

Know a better way?

If you can do better, submit your command here.

What others think

You know you're rewriting the file on each output, right?

Comment by ubersoldat 383 weeks and 5 days ago

@ubersoldat: No, he isn't. The output redirection is evaluated by the shell only once.

However, this can be done much easier, safer and more efficient with zsh (this is one of the many reasons why I love zsh):

cat **/*.ext > file.txt
Comment by inof 383 weeks and 5 days ago

I think the argument to -name should be quoted, otherwise the shell is needlessly expanding it.

@inof I can see why one might think that you're cat-appending to the same file multiple times because the output redirection is put before the end of the argument to the -exec option. So a more readable and error-free form of the command would be:

find . -type f -name "*.ext" -exec cat {} \; >filename.txt

so that the arguments to find and the shell syntax are clearly separated. Bash 4.0 has added support for ** globbing, although this won't obsolete find :-).

Comment by bwoodacre 383 weeks and 5 days ago

Good stuff guys, your comments assisted me to pull text out of binary files from multiple files and directories by essentially just replacing cat with strings. Thanks for sharing your knowledge.

find . -type f -name "*.*" -exec strings {} \; >alltext.out

Comment by gromburger 366 weeks and 6 days ago

Hi guys! Can you please explain me the purpose of the final backslash just after file.txt?

Comment by clapclash 213 weeks and 4 days ago

I was doing "tree -fi | grep .txt | xargs cat &> output.txt". I like the globbing.

Comment by qdrizh 97 weeks and 5 days ago

Your point of view

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