NAME

       encoding - Manipulate encodings

SYNOPSIS

       encoding option ?arg arg ...?
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INTRODUCTION

       Strings  in  Tcl  are  encoded using 16-bit Unicode characters.  Different operating system interfaces or
       applications may generate strings in other encodings such as Shift-JIS.  The encoding  command  helps  to
       bridge the gap between Unicode and these other formats.

DESCRIPTION

       Performs one of several encoding related operations, depending on option.  The legal options are:

       encoding convertfrom ?encoding? data
              Convert data to Unicode from the specified encoding.  The characters in data are treated as binary
              data  where  the lower 8-bits of each character is taken as a single byte.  The resulting sequence
              of bytes is treated as a string in the specified encoding.  If  encoding  is  not  specified,  the
              current system encoding is used.

       encoding convertto ?encoding? string
              Convert  string  from  Unicode  to the specified encoding.  The result is a sequence of bytes that
              represents the converted string.  Each byte is stored in the lower 8-bits of a Unicode  character.
              If encoding is not specified, the current system encoding is used.

       encoding dirs ?directoryList?
              Tcl can load encoding data files from the file system that describe additional encodings for it to 2
              work  with.  This  command  sets  the  search  path  for  *.enc encoding data files to the list of 2
              directories directoryList. If directoryList is omitted then the command returns the  current  list 2
              of  directories  that  make up the search path. It is an error for directoryList to not be a valid 2
              list. If, when a search for an encoding data file is happening, an element in  directoryList  does 2
              not refer to a readable, searchable directory, that element is ignored.

       encoding names
              Returns a list containing the names of all of the encodings that are currently available.

       encoding system ?encoding?
              Set  the  system encoding to encoding. If encoding is omitted then the command returns the current
              system encoding.  The system encoding is used whenever Tcl passes strings to system calls.

EXAMPLE

       It is common practice to write script files using a text  editor  that  produces  output  in  the  euc-jp
       encoding,  which  represents  the  ASCII  characters as singe bytes and Japanese characters as two bytes.
       This makes it easy to embed literal strings that correspond to non-ASCII characters by simply typing  the
       strings in place in the script.  However, because the source command always reads files using the current
       system  encoding,  Tcl  will only source such files correctly when the encoding used to write the file is
       the same.  This tends not to be true in an internationalized setting.  For example, if such  a  file  was
       sourced  in  North America (where the ISO8859-1 is normally used), each byte in the file would be treated
       as a separate character that maps to the 00 page in Unicode.  The resulting Tcl strings will not  contain
       the  expected  Japanese  characters.   Instead,  they  will contain a sequence of Latin-1 characters that
       correspond to the bytes of the original string.  The encoding command can be used to convert this  string
       to the expected Japanese Unicode characters.  For example,
              set s [encoding convertfrom euc-jp "\xA4\xCF"]
       would return the Unicode string “\u306F”, which is the Hiragana letter HA.

SEE ALSO

       Tcl_GetEncoding(3tcl)

KEYWORDS

       encoding

Tcl                                                    8.1                                        encoding(3tcl)