uconv(1) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | CALLBACKS | EXAMPLES | CAVEATS AND BUGS | AUTHORS | VERSION | COPYRIGHT | SEE ALSO | COLOPHON

UCONV(1)                     ICU 67.1 Manual                    UCONV(1)

NAME         top

       uconv - convert data from one encoding to another

SYNOPSIS         top

       uconv [ -h, -?, --help ] [ -V, --version ] [ -s, --silent ] [ -v,
       --verbose ] [ -l, --list | -l, --list-code code | --default-code
       | -L, --list-transliterators ] [ --canon ] [ -x transliteration ]
       [ --to-callback callback | -c ] [ --from-callback callback | -i ]
       [ --callback callback ] [ --fallback | --no-fallback ] [ -b,
       --block-size size ] [ -f, --from-code encoding ] [ -t, --to-code
       encoding ] [ --add-signature ] [ --remove-signature ] [ -o,
       --output file ] [ file...  ]

DESCRIPTION         top

       uconv converts, or transcodes, each given file (or its standard
       input if no file is specified) from one encoding to another.  The
       transcoding is done using Unicode as a pivot encoding (i.e. the
       data are first transcoded from their original encoding to
       Unicode, and then from Unicode to the destination encoding).

       If an encoding is not specified or is -, the default encoding is
       used. Thus, calling uconv with no encoding provides an easy way
       to validate and sanitize data files for further consumption by
       tools requiring data in the default encoding.

       When calling uconv, it is possible to specify callbacks that are
       used to handle invalid characters in the input, or characters
       that cannot be transcoded to the destination encoding. Some
       encodings, for example, offer a default substitution character
       that can be used to represent the occurrence of such characters
       in the input. Other callbacks offer a useful visual
       representation of the invalid data.

       uconv can also run the specified transliteration on the
       transcoded data, in which case transliteration will happen as an
       intermediate step, after the data have been transcoded to
       Unicode.  The transliteration can be either a list of semicolon-
       separated transliterator names, or an arbitrarily complex set of
       rules in the ICU transliteration rules format.

       For transcoding purposes, uconv options are compatible with those
       of iconv(1), making it easy to replace it in scripts. It is not
       necessarily the case, however, that the encoding names used by
       uconv and ICU are the same as the ones used by iconv(1).  Also,
       options that provide informational data, such as the -l, --list
       one offered by some iconv(1) variants such as GNU's, produce data
       in a slightly different and easier to parse format.

OPTIONS         top

       -h, -?, --help
              Print help about usage and exit.

       -V, --version
              Print the version of uconv and exit.

       -s, --silent
              Suppress messages during execution.

       -v, --verbose
              Display extra informative messages during execution.

       -l, --list
              List all the available encodings and exit.

       -l, --list-code code
              List only the code encoding and exit. If code is not a
              proper encoding, exit with an error.

       --default-code
              List only the name of the default encoding and exit.

       -L, --list-transliterators
              List all the available transliterators and exit.

       --canon
              If used with -l, --list or --default-code, the list of
              encodings is produced in a format compatible with
              convrtrs.txt(5).  If used with -L, --list-transliterators,
              print only one transliterator name per line.

       -x transliteration
              Run the given transliteration on the transcoded Unicode
              data, and use the transliterated data as input for the
              transcoding to the destination encoding.

       --to-callback callback
              Use callback to handle characters that cannot be
              transcoded to the destination encoding. See section
              CALLBACKS for details on valid callbacks.

       -c     Omit invalid characters from the output.  Same as
              --to-callback skip.

       --from-callback callback
              Use callback to handle characters that cannot be
              transcoded from the original encoding. See section
              CALLBACKS for details on valid callbacks.

       -i     Ignore invalid sequences in the input.  Same as
              --from-callback skip.

       --callback callback
              Use callback to handle both characters that cannot be
              transcoded from the original encoding and characters that
              cannot be transcoded to the destination encoding. See
              section CALLBACKS for details on valid callbacks.

       --fallback
              Use the fallback mapping when transcoding from Unicode to
              the destination encoding.

       --no-fallback
              Do not use the fallback mapping when transcoding from
              Unicode to the destination encoding.  This is the default.

       -b, --block-size size
              Read input in blocks of size bytes at a time. The default
              block size is 4096.

       -f, --from-code encoding
              Set the original encoding of the data to encoding.

       -t, --to-code encoding
              Transcode the data to encoding.

       --add-signature
              Add a U+FEFF Unicode signature character (BOM) if the
              output charset supports it and does not add one anyway.

       --remove-signature
              Remove a U+FEFF Unicode signature character (BOM).

       -o, --output file
              Write the transcoded data to file.

CALLBACKS         top

       uconv supports specifying callbacks to handle invalid data.
       Callbacks can be set for both directions of transcoding: from the
       original encoding to Unicode, with the --from-callback option,
       and from Unicode to the destination encoding, with the
       --to-callback option.

       The following is a list of valid callback names, along with a
       description of their behavior. The list of callbacks actually
       supported by uconv is displayed when it is called with -h,
       --help.

       substitute
              Write the encoding's substitute sequence, or the Unicode
              replacement character U+FFFD when transcoding to Unicode.

       skip   Ignore the invalid data.

       stop   Stop with an error when encountering invalid data.  This
              is the default callback.

       escape Same as escape-icu.

       escape-icu
              Replace the missing characters with a string of the format
              %Uhhhh for plane 0 characters, and %Uhhhh%Uhhhh for planes
              1 and above characters, where hhhh is the hexadecimal
              value of one of the UTF-16 code units representing the
              character. Characters from planes 1 and above are written
              as a pair of UTF-16 surrogate code units.

       escape-java
              Replace the missing characters with a string of the format
              \uhhhh for plane 0 characters, and \uhhhh\uhhhh for planes
              1 and above characters, where hhhh is the hexadecimal
              value of one of the UTF-16 code units representing the
              character. Characters from planes 1 and above are written
              as a pair of UTF-16 surrogate code units.

       escape-c
              Replace the missing characters with a string of the format
              \uhhhh for plane 0 characters, and \Uhhhhhhhh for planes 1
              and above characters, where hhhh and hhhhhhhh are the
              hexadecimal values of the Unicode codepoint.

       escape-xml
              Same as escape-xml-hex.

       escape-xml-hex
              Replace the missing characters with a string of the format
              &#xhhhh;, where hhhh is the hexadecimal value of the
              Unicode codepoint.

       escape-xml-dec
              Replace the missing characters with a string of the format
              &#nnnn;, where nnnn is the decimal value of the Unicode
              codepoint.

       escape-unicode
              Replace the missing characters with a string of the format
              {U+hhhh}, where hhhh is the hexadecimal value of the
              Unicode codepoint.  That hexadecimal string is of variable
              length and can use from 4 to 6 digits.  This is the format
              universally used to denote a Unicode codepoint in the
              literature, delimited by curly braces for easy recognition
              of those substitutions in the output.

EXAMPLES         top

       Convert data from a given encoding to the platform encoding:

           $ uconv -f encoding

       Check if a file contains valid data for a given encoding:

           $ uconv -f encoding -c file >/dev/null

       Convert a UTF-8 file to a given encoding and ensure that the
       resulting text is good for any version of HTML:

           $ uconv -f utf-8 -t encoding \
               --callback escape-xml-dec file

       Display the names of the Unicode code points in a UTF-file:

           $ uconv -f utf-8 -x any-name file

       Print the name of a Unicode code point whose value is known
       (U+30AB in this example):

           $ echo '\u30ab' | uconv -x 'hex-any; any-name'; echo
           {KATAKANA LETTER KA}{LINE FEED}
           $

       (The names are delimited by curly braces.  Also, the name of the
       line terminator is also displayed.)

       Normalize UTF-8 data using Unicode NFKC, remove all control
       characters, and map Katakana to Hiragana:

           $ uconv -f utf-8 -t utf-8 \
                 -x '::nfkc; [:Cc:] >; ::katakana-hiragana;'

CAVEATS AND BUGS         top

       uconv does report errors as occurring at the first invalid byte
       encountered. This may be confusing to users of GNU iconv(1),
       which reports errors as occurring at the first byte of an invalid
       sequence. For multi-byte character sets or encodings, this means
       that uconv error positions may be at a later offset in the input
       stream than would be the case with GNU iconv(1).

       The reporting of error positions when a transliterator is used
       may be inaccurate or unavailable, in which case uconv will report
       the offset in the output stream at which the error occurred.

AUTHORS         top

       Jonas Utterstroem
       Yves Arrouye

VERSION         top

       67.1

COPYRIGHT         top

       Copyright (C) 2000-2005 IBM, Inc. and others.

SEE ALSO         top

       iconv(1)

COLOPHON         top

       This page is part of the ICU (International Components for
       Unicode) project.  Information about the project can be found at
       ⟨http://site.icu-project.org/home⟩.  If you have a bug report for
       this manual page, see ⟨http://site.icu-project.org/bugs⟩.  This
       page was obtained from the project's upstream Git repository
       ⟨https://github.com/unicode-org/icu⟩ on 2021-04-01.  (At that
       time, the date of the most recent commit that was found in the
       repository was 2021-03-31.)  If you discover any rendering
       problems in this HTML version of the page, or you believe there
       is a better or more up-to-date source for the page, or you have
       corrections or improvements to the information in this COLOPHON
       (which is not part of the original manual page), send a mail to
       man-pages@man7.org

ICU MANPAGE                    2005-jul-1                       UCONV(1)

Pages that refer to this page: iconv(1)