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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' *
2010-12-09 18:50:17
User: Juev
Functions: rename
Batch rename extension of all files in a folder, in the example from .txt to .md


There are 5 alternatives - vote for the best!

Terminal - Alternatives
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 's/\.txt$/\.md$/i' *
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?

If you can do better, submit your command here.

What others think

Should be rename 's/txt$/md/i' *.txt

instead of rename 's/.txt/.md/i' *

to make sure it doesn't accidentally match ".txt" somewhere in the middle of a filename.

Comment by mobilediesel 294 weeks ago

@mobilediesel Yes, you are right. I haven't thought of it. Thanks big for the amendment!

Comment by Juev 294 weeks ago

Also, if you have s/.txt/.md/i, you want to escape the periods; they're metachars in REs. Otherwise it'll replace "asdftxt" with "asd.md"

Comment by kaedenn 293 weeks and 6 days ago

Your point of view

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