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I have files with invalid characters like these


It is a Æ where something have gone wrong in the filename.

Is there a way to just remove all invalid characters?

or could tr be used somehow?

echo "009_-_�%86ndringshåndtering.html" | tr ???
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The characters probably aren't "invalid", else the filesystem wouldn't store them (unless you did something really nasty to the FS). Have you tried changing your locale (e.g. to UTF8) to display the names correctly? – James O'Gorman Jan 10 '12 at 14:29
up vote 14 down vote accepted

One way would be with sed:

mv 'file' $(echo 'file' | sed -e 's/[^A-Za-z0-9._-]/_/g')

Replace file with your filename, of course. This will replace anything that isn't a letter, number, period, underscore, or dash with an underscore. You can add or remove characters to keep as you like, and/or change the replacement character to anything else, or nothing at all.

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I used: f='file'; mv 'file' ${f//[^A-Za-z0-9._-]/_} – Louis Oct 7 '15 at 15:05

I assume you are on Linux box and the files were made on a Windows box. Linux uses UTF-8 as the character encoding for filenames, while Windows uses something else. I think this is the cause of the problem.

I would use "convmv". This is a tool that can convert filenames from one character encoding to another. For Western Europe one of these normally works:

convmv -r -f windows-1252 -t UTF-8 .
convmv -r -f ISO-8859-1 -t UTF-8 .
convmv -r -f cp-850 -t UTF-8 .

If you need to install it on a Debian based Linux you can do so by running:

sudo apt-get install convmv

It works for me every time and it does recover the original filename.

Source: LeaseWebLabs

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I assume you mean you want to traverse the filesystem and fix all such files?

Here's the way I'd do it

find /path/to/files -type f -print0 | \
perl -n0e '$new = $_; if($new =~ s/[^[:ascii:]]/_/g) {
  print("Renaming $_ to $new\n"); rename($_, $new);

That would find all files with non-ascii characters and replace those characters with underscores (_). Use caution though, if a file with the new name already exists, it'll overwrite it. The script can be modified to check for such a case, but I didnt put that in to keep it simple.

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Following answers at, You can use:

rename -n 's/[^\x00-\x7F]//g' *

where * matches the files you want to rename. If you want to do it over multiple directories, you can do something like:

find . -exec rename 's/[^\x00-\x7F]//g' "{}" \;

You can use the -n argument to rename to do a dry run, and see what would be changed, without changing it.

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Is there a way to modify this to keep foreign characters such as ü and ä for example? – Elder Geek Feb 6 at 22:51

If you want to handle embedded newlines, multibyte characters, spaces, leading dashes, backslashes and spaces you are going to need something more robust, see this answer:

I put the script up on if anyone is interested: r-n-f-bash-rename-script

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This shell script sanitizes a directory recursively, to make files portable between Linux/Windows and FAT/NTFS/exFAT. It removes control characters, /:*?"<>\| and some reserved Windows names like COM0.

sanitize() {
  shopt -s extglob;

  filename=$(basename "$1")
  directory=$(dirname "$1")

  filename_clean=$(echo "$filename" | sed -e 's/[\\/:\*\?"<>\|\x01-\x1F\x7F]//g' -e 's/^\(nul\|prn\|con\|lpt[0-9]\|com[0-9]\|aux\)\(\.\|$\)//i' -e 's/^\.*$//' -e 's/^$/NONAME/')

  if (test "$filename" != "$filename_clean")
    mv -v "$1" "$directory/$filename_clean"

export -f sanitize

sanitize_dir() {
find $1 -depth -exec bash -c 'sanitize "$0"' {} \;

sanitize_dir '/path/to/somewhere'

Linux is less restrictive in theory (/ and \0 are strictly forbidden in filenames) but in practice several characters interfere with bash commands (like *...) so they should be also be avoided in filenames.

Great sources for file naming restrictions:

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