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 "Cu2088Hu2081u2080Nu2084Ou2082"]
       % set encoded [ascii85::encode $chemical]
       6fN]R8E,5PiduUiduhZidua
       % 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://sourceforge.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 Gavilan

base64									1.0								ascii85(n)