Using convmv

A simple and reliable way to rename files and/or directories to lowercase is using convmv.
To lowercase a file or directory use:

convmv --notest --lower SomeFileName


One can also use -r to make conversion recursive. When files which have to be converted have non-ASCII characters, it's required to enter the used charset of the filenames. Without knowledge of the used charset it would be impossible to reliably lowercase:

convmv --notest --lower -f utf-8 File_Ähh_with_Ümlauts


Using renamexm

A simple way to rename files and/or directories to lowercase is using renamxm from rename

To lowercase a single file or directory use:


renamexm --lowcase ''name''

To recursively lowercase a directory and its contents use:


renamexm --lowcase --recursive ''name''

To recursively lowercase the contents of a directory, but not the directory itself, add a trailing slash to the directory name:
renamexm --lowcase --recursive ''name/''

Using mmv

mmv allows you to move, copy, and rename multiple files using wildcards and regular expressions.

To lowercase all files in the current directory, use:
mmv "*" "#l1"

To lowercase all files and directories in the current directory, use:
mmv -r "*" "#l1"

Bash script

Here is a nice little script from http://lists.suse.com/archive/suse-linux-e/2001-Jul/2593.html to lowercase-ify files and/or folders:

lowerit.sh

#!/bin/sh
#
# January 22, 1998
#
# Some ideas borrowed from the Tips-HOWTO. Modifications by BJ Goodwin
# .
#
# Copyleft 1998
# All Beers Consumed.
#
if [ ! $1 ]; then
echo "Not enough arguments. Try $0 -h for options."
exit 1
fi
if [ $1 = "-f" -o $1 = "-d" -o $1 = "-a" -o $1 = "-h" ]; then
:
else
echo "$0: Invalid argument. Try $0 -h for help."
exit 1
fi
if [ $1 = "-f" ]; then
for x in `ls`
do
if [ ! -f $x ]; then
continue
fi

convert=`echo $x | tr '[A-Z]' '[a-z]'`

if [ $convert != $x ]; then
mv -i $x $convert
fi
done
exit
fi
if [ $1 = "-d" ]; then
for x in `ls`
do
if [ ! -d $x ]; then
continue
fi

convert=`echo $x | tr '[A-Z]' '[a-z]'`

if [ $convert != $x ]; then
mv -i $x $convert
fi
done
exit
fi
if [ $1 = "-a" ]; then
for x in `ls`
do
if [ -f $x -a -d $x ]; then
continue
fi

convert=`echo $x | tr '[A-Z]' '[a-z]'`

if [ $convert != $x ]; then
mv -i $x $convert
fi
done
exit
fi
if [ $1 = "-h" ]; then
echo "-----------------------------------------------------------"
echo "lowercase v1.0 - Convert files or directories to lowercase."
echo "-----------------------------------------------------------"
echo "Usage: $0 "
echo
echo "Options:"
echo " -f = All files in current directory."
echo " -d = All directories in current directory."
echo " -a = All files AND directories in current directory."
echo " -h = This help screen."
echo
echo "Notes: If a lowercase directory already exists that has the same"
echo " name as the uppercase directory, the uppercase will be"
echo " MOVED to the lowercase directory without confirmation."
exit
fi