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
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 Trackers [
http://core.tcl.tk/tcllib/reportlist]. 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 Gavilán