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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
2
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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 \;

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Know a better way?

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What others think

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

Comment by ubersoldat 38 weeks and 3 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 38 weeks and 3 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 38 weeks and 3 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 21 weeks and 3 days ago

Your point of view

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