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       convmv - converts filenames from one encoding to another


       convmv [options] FILE(S) ... DIRECTORY(S)


       -f ENCODING
           specify the current encoding of the filename(s) from which should
           be converted

       -t ENCODING
           specify the encoding to which the filename(s) should be converted

       -i  interactive mode (ask y/n for each action)

       -r  recursively go through directories

           target files will be normalization form C for UTF-8 (Linux etc.)

           target files will be normalization form D for UTF-8 (OS X etc.).

       --qfrom , --qto
           be more quiet about the "from" or "to" of a rename (if it screws up
           your terminal e.g.). This will in fact do nothing else than replace
           any non-ASCII character (bytewise) with ? and any control character
           with * on printout, this does not affect rename operation itself.

       --exec command
           execute the given command. You have to quote the command and #1
           will be substituted by the old, #2 by the new filename. Using this
           option link targets will stay untouched.


           convmv -f latin1 -t utf-8 -r --exec "echo #1 should be renamed to
           #2" path/to/files

           list all available encodings. To get support for more Chinese or
           Japanese encodings install the Perl HanExtra or JIS2K Encode

           keep memory footprint low by not creating a hash of all files. This
           disables checking if symlink targets are in subtree. Symlink target
           pointers will be converted regardlessly. If you convert multiple
           hundredthousands or millions of files the memory usage of convmv
           might grow quite high. This option would help you out in that case.

           by default convmv will detect if a filename is already UTF8 encoded
           and will skip this file if conversion from some charset to UTF8
           should be performed.  "--nosmart" will also force conversion to
           UTF-8 for such files, which might result in "double encoded UTF-8"
           (see section below).

           Needed to actually rename the files. By default convmv will just
           print what it wants to do.

       --parsable This is not implemented yet.
           if the file to which shall be renamed already exists, it will be
           overwritten if the other file content is equal.

           this option will remove this ugly % hex sequences from filenames
           and turn them into (hopefully) nicer 8-bit characters. After
           --unescape you might want to do a charset conversion. This
           sequences like %20 etc. are sometimes produced when downloading via
           http or ftp.

       --upper , --lower
           turn filenames into all upper or all lower case. When the file is
           not ASCII-encoded, convmv expects a charset to be entered via the
           -f switch.

           care about the dotless i/I issue. A lowercase version of "I" will
           also be dotless while an uppercase version of "i" will also be
           dotted. This is an issue for Turkish and Azeri.

           By the way: The superscript dot of the letter i was added in the
           Middle Ages to distinguish the letter (in manuscripts) from
           adjacent vertical strokes in such letters as u, m, and n. J is a
           variant form of i which emerged at this time and subsequently
           became a separate letter.

           print a short summary of available options


       convmv is meant to help convert a single filename, a directory tree and
       the contained files or a whole filesystem into a different encoding. It
       just converts the filenames, not the content of the files. A special
       feature of convmv is that it also takes care of symlinks, also converts
       the symlink target pointer in case the symlink target is being
       converted, too.

       All this comes in very handy when one wants to switch over from old
       8-bit locales to UTF-8 locales. It is also possible to convert
       directories to UTF-8 which are already partly UTF-8 encoded. convmv is
       able to detect if certain files are UTF-8 encoded and will skip them by
       default. To turn this smartness off use the "--nosmart" switch.

   Filesystem issues
       Almost all POSIX filesystems do not care about how filenames are
       encoded, here are some exceptions:

       HFS+ on OS X / Darwin

       Linux and (most?) other Unix-like operating systems use the so called
       normalization form C (NFC) for its UTF-8 encoding by default but do not
       enforce this.  Darwin, the base of the Macintosh OS enforces
       normalization form D (NFD), where a few characters are encoded in a
       different way. On OS X it’s not possible to create NFC UTF-8 filenames
       because this is prevented at filesystem layer.  On HFS+ filenames are
       internally stored in UTF-16 and when converted back to UTF-8, for the
       underlying BSD system to be handable, NFD is created.  See for defails. I think
       it was a very bad idea and breaks many things under OS X which expect a
       normal POSIX conforming system. Anywhere else convmv is able to convert
       files from NFC to NFD or vice versa which makes interoperability with
       such systems a lot easier.


       If people mount JFS partitions with iocharset=utf8, there is a similar
       problem, because JFS is designed to store filenames internally in
       UTF-16, too; that is because Linux’ JFS is really JFS2, which was a
       rewrite of JFS for OS/2. JFS partitions should always be mounted with
       iocharset=iso8859-1, which is also the default with recent 2.6.6
       kernels. If this is not done, JFS does not behave like a POSIX
       filesystem and it might happen that certain files cannot be created at
       all, for example filenames in ISO-8859-1 encoding. Only when
       interoperation with OS/2 is needed iocharset should be set according to
       your used locale charmap.


       Despite other POSIX filesystems RFC3530 (NFS 4) mandates UTF-8 but also
       says: "The nfs4_cs_prep profile does not specify a normalization form.
       A later revision of this specification may specify a particular
       normalization form." In other words, if you want to use NFS4 you might
       find the conversion and normalization features of convmv quite useful.

       FAT/VFAT and NTFS

       NTFS and VFAT (for long filenames) use UTF-16 internally to store
       filenames.  You should not need to convert filenames if you mount one
       of those filesystems.  Use appropriate mount options instead!

   How to undo double UTF-8 (or other) encoded filenames
       Sometimes it might happen that you "double-encoded" certain filenames,
       for example the file names already were UTF-8 encoded and you
       accidently did another conversion from some charset to UTF-8. You can
       simply undo that by converting that the other way round. The from-
       charset has to be UTF-8 and the to-charset has to be the from-charset
       you previously accidently used. You should check to get the correct
       results by doing the conversion without "--notest" before, also the
       "--qfrom" option might be helpful, because the double utf-8 file names
       might screw up your terminal if they are being printed - they often
       contain control sequences which do funny things with your terminal
       window. If you are not sure about the charset which was accidently
       converted from, using "--qfrom" is a good way to fiddle out the
       required encoding without destroying the file names finally.

   How to repair Samba files
       When in the smb.conf (of Samba 2.x) there hasn’t been set a correct
       "character set" variable, files which are created from Win* clients are
       being created in the client’s codepage, e.g. cp850 for western european
       languages. As a result of that the files which contain non-ASCII
       characters are screwed up if you "ls" them on the Unix server. If you
       change the "character set" variable afterwards to iso8859-1, newly
       created files are okay, but the old files are still screwed up in the
       Windows encoding. In this case convmv can also be used to convert the
       old Samba-shared files from cp850 to iso8859-1.

       By the way: Samba 3.x finally maps to UTF-8 filenames by default, so
       also when you migrate from Samba 2 to Samba 3 you might have to convert
       your file names.

   Netatalk interoperability issues
       When Netatalk is being switched to UTF-8 which is supported in version
       2 then it is NOT sufficient to rename the file names. There needs to be
       done more. See
       and the uniconv utility of Netatalk for details.


       locale(1) utf-8(7) charsets(7)


       no bugs or fleas known


       Bjoern JACKE

       Send mail to bjoern [at] for bug reports and suggestions.