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2011-03-12 - Confoo 2011 presentation
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Batch rename extension of all files in a folder, in the example from .txt to .md

Terminal - Batch rename extension of all files in a folder, in the example from .txt to .md
rename 's/\.txt$/\.md$/i' *
2010-12-18 15:27:58
User: Juev
Functions: rename
Batch rename extension of all files in a folder, in the example from .txt to .md


There are 7 alternatives - vote for the best!

Terminal - Alternatives
rename 's/.txt/.md/i' *
mmv "*.txt" "#1.md"
2010-12-09 19:14:07
User: houghi
Tags: batch rename

Batch rename extension of all files in a folder, in the example from .txt to .md

mmv most likely must be installed, but is very powerfull when you want to move/copy/append/link multiple files by wildcard patterns.

for f in *.txt;do mv ${f%txt}{txt,md}; done
2010-12-09 18:55:15
User: mobilediesel
Functions: mv
Tags: batch rename

Same thing using bash built-in features instead of a sub-shell.

for f in *.txt; do mv $f `basename $f .txt`.md; done;
2010-12-09 18:29:17
User: vranx
Functions: mv
Tags: batch rename

Batch rename extension of all files in a folder, in the example from .txt to .md

rename *.JPG *.jpg
2014-03-05 14:54:33
User: gtoal
Functions: rename
Tags: batch rename

# Limited and very hacky wildcard rename

# works for rename *.ext *.other

# and for rename file.* other.*

# but fails for rename file*ext other*other and many more

# Might be good to merge this technique with mmv command...

mv-helper() {

argv="`history 1 | perl -pe 's/^ *[0-9]+ +[^ ]+ //'`"

files="`echo \"$argv\"|sed -e \"s/ .*//\"`"

str="`history 1 | perl -pe 's/^ *[0-9]+ +[^ ]+ //' | tr -d \*`"

set -- $str

for file in $files


echo mv $file `echo $file|sed -e "s/$1/$2/"`

mv $file `echo $file|sed -e "s/$1/$2/"`



alias rename='mv-helper #'

Know a better way?

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What others think

You don't need to escape the second part; it's not a pattern. In fact, I don't think that'll produce the correct result.

Comment by kaedenn 193 weeks and 2 days ago

@kaedenn Thank you very much! I had not thought about it.

Comment by Juev 193 weeks and 1 day ago

Did you even try this? :) At least with my version you get a "Final $ should be \$ or $name at (eval 1) line 1, within string".

The replacement shouldn't have any regexy stuff in it except backreferences -- the dot doesn't need escaping (as pointed out by kaedenn) and the dollar doesn't mean anything.

So you want

rename 's/\.txt$/.md/i' *
Comment by tremby 192 weeks and 2 days ago

Your point of view

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