tcl::transform::rot(3tcReflected/virtual channel supptcl::transform::rot(3tcl)
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NAME
tcl::transform::rot - rot-encryption
SYNOPSIS
package require Tcl 8.6
package require tcl::transform::core ?1?
package require tcl::transform::rot ?1?
::tcl::transform::rot chan key
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DESCRIPTION
The tcl::transform::rot package provides a command creating a channel
transformation which performs primitive encryption (on writing) and de-
cryption (on reading) on the alphabetic characters. The algorithm is
the Caesar-cipher, a specific variant of which is rot13.
A related transformations in this module is tcl::transform::otp.
The internal TclOO class implementing the transform handler is a sub-
class of the tcl::transform::core framework.
API
::tcl::transform::rot chan key
This command creates a rot encryption transformation on top of
the channel chan and returns its handle.
The "key" specifies how far characters are rotated in the alpha-
bet, and is wrapped to the range "0...25".
Note that this transformation affects only bytes in the ranges
ASCII 65...90, and 97...122, i.e. the upper- and lower-case al-
phabetic characters, i.e. "A...Z" and "a...z". All other bytes
are passed through unchanged.
BUGS, IDEAS, FEEDBACK
This document, and the package it describes, will undoubtedly contain
bugs and other problems. Please report such in the category virtchan-
nel 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.
When proposing code changes, please provide unified diffs, i.e the out-
put of diff -u.
Note further that attachments are strongly preferred over inlined
patches. Attachments can be made by going to the Edit form of the
ticket immediately after its creation, and then using the left-most
button in the secondary navigation bar.
KEYWORDS
caesar cipher, channel transformation, cipher, decryption, encryption,
reflected channel, rot, rot13, tip 230, transformation, virtual channel
CATEGORY
Channels
COPYRIGHT
Copyright (c) 2009 Andreas Kupries <andreas_kupries@users.sourceforge.net>
tcllib 1 tcl::transform::rot(3tcl)