Linux: rename or change extension of multiple files

When you need to bulk rename files you can not call "mv *.foo *.bar" to change the extension of all .foo files to bar (because bash resolves wildcards and replaces them with the list of matched files).

This works on linuxes who use the Perl version of the rename command (like Ubuntu):

rename 's/\.foo$/\.bar/' *

You can also use this to rename other parts of the file, e.g. from flag_en.png, flag_de.png etc. to just en.png or de.png:

rename 's/^flag_//' *

Note that we used $ and ^ to explicitly look at the end and start of the filenames.

Arne Hartherz

makandra.com

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Last edit

Over 7 years ago

Henning Koch

Keywords

bash, shell

License

Source code in this card is licensed under the MIT License.

Grep the number of occurences in a file, counting multiple hits per line

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grep -c "something" filename

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Show the current Git branch on your Bash prompt

Append this to your ~/.bashrc:

export PS1='\[\033[01;32m\]\h\[\033[01;34m\] \w\[\033[31m\]$(__git_ps1 "(%s)") \[\033[01;34m\]$\[\033[00m\] '

Reload the changes by saying

source ~/.bashrc

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You know there is the du command to fetch the disk usage of a directory (“.” in this example). By default, output is sorted by directory name, not size:

du -h --max-depth=1 .
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3.1M ./c
500M ./d
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Truncate files to zero length

This will reduce the filesize of foo and bar to 0 bytes:

truncate -s0 foo bar

If the files do not exist they will be created.

You can use this to easily truncate your application's log files:

truncate -s0 log/*.log

Posted by Arne Hartherz to makandra dev (2011-02-16 14:31)

Linux: rename or change extension of multiple files

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