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ascii85(n)                          Text encoding & decoding binary data                          ascii85(n)



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NAME
       ascii85 - ascii85-encode/decode binary data

SYNOPSIS
       package require Tcl  8.4

       package require ascii85  ?1.0?

       ::ascii85::encode ?-maxlen maxlen? ?-wrapchar wrapchar? string

       ::ascii85::decode string

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DESCRIPTION
       This package provides procedures to encode binary data into ascii85 and back.

       ::ascii85::encode ?-maxlen maxlen? ?-wrapchar wrapchar? string
              Ascii85  encodes the given binary string and returns the encoded result. Inserts the character
              wrapchar every maxlen characters of output. wrapchar defaults to newline. maxlen  defaults  to
              76.

              Note  well: If your string is not simple ascii you should fix the string encoding before doing
              ascii85 encoding. See the examples.

              The command will throw an error for negative values of maxlen, or if maxlen is not an  integer
              number.

       ::ascii85::decode string
              Ascii85  decodes the given string and returns the binary data.  The decoder ignores whitespace
              in the string, as well as tabs and newlines.


EXAMPLES
       % ascii85::encode "Hello, world"
       87cURD_*#TDfTZ)


       % ascii85::encode [string repeat xyz 24]
       G^4U[H$X^\H?a^]G^4U[H$X^\H?a^]G^4U[H$X^\H?a^]G^4U[H$X^\H?a^]G^4U[H$X^\H?a^]G
       ^4U[H$X^\H?a^]
       % ascii85::encode -wrapchar "" [string repeat xyz 24]
       G^4U[H$X^\H?a^]G^4U[H$X^\H?a^]G^4U[H$X^\H?a^]G^4U[H$X^\H?a^]G^4U[H$X^\H?a^]G^4U[H$X^\H?a^]


       # NOTE: ascii85 encodes BINARY strings.
       % set chemical [encoding convertto utf-8 "C\u2088H\u2081\u2080N\u2084O\u2082"]
       % set encoded [ascii85::encode $chemical]
       6fN]R8E,5Pidu\UiduhZidua
       % set caffeine [encoding convertfrom utf-8 [ascii85::decode $encoded]]


REFERENCES
       [1]    http://en.wikipedia.org/wiki/Ascii85

       [2]    Postscript     Language      Reference      Manual,      3rd      Edition,      page      131.
              http://www.adobe.com/devnet/postscript/pdfs/PLRM.pdf


BUGS, IDEAS, FEEDBACK
       This  document,  and  the  package  it  describes,  will undoubtedly contain bugs and other problems.
       Please  report  such  in  the  category  base64   of   the   Tcllib   SF   Trackers   [http://source -
       forge.net/tracker/? group_id=12883].   Please  also report any ideas for enhancements you may have for
       either package and/or documentation.

KEYWORDS
       ascii85, encoding

CATEGORY
       Text processing

COPYRIGHT
       Copyright (c) 2010, Emiliano Gavil~,n




base64                                               1.0                                          ascii85(n)