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base64(n)                           Text encoding & decoding binary data                           base64(n)



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NAME
       base64 - base64-encode/decode binary data

SYNOPSIS
       package require Tcl  8

       package require base64  ?2.4.2?

       ::base64::encode ?-maxlen maxlen? ?-wrapchar wrapchar? string

       ::base64::decode string

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DESCRIPTION
       This package provides procedures to encode binary data into base64 and back.

       ::base64::encode ?-maxlen maxlen? ?-wrapchar wrapchar? string
              Base64  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
              base64 encoding. See the examples.

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

       ::base64::decode string
              Base64  decodes  the given string and returns the binary data.  The decoder ignores whitespace
              in the string.


EXAMPLES
       % base64::encode "Hello, world"
       SGVsbG8sIHdvcmxk


       % base64::encode [string repeat xyz 20]
       eHl6eHl6eHl6eHl6eHl6eHl6eHl6eHl6eHl6eHl6eHl6eHl6eHl6eHl6eHl6
       eHl6eHl6eHl6
       % base64::encode -wrapchar "" [string repeat xyz 20]
       eHl6eHl6eHl6eHl6eHl6eHl6eHl6eHl6eHl6eHl6eHl6eHl6eHl6eHl6eHl6eHl6eHl6eHl6


       # NOTE: base64 encodes BINARY strings.
       % set chemical [encoding convertto utf-8 "C\u2088H\u2081\u2080N\u2084O\u2082"]
       % set encoded [base64::encode $chemical]
       Q+KCiEjigoHigoBO4oKET+KCgg==
       % set caffeine [encoding convertfrom utf-8 [base64::decode $encoded]]


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
       base64, encoding

CATEGORY
       Text processing

COPYRIGHT
       Copyright (c) 2000, Eric Melski
       Copyright (c) 2001, Miguel Sofer




base64                                              2.4.2                                          base64(n)