rot13

README

rot13 encoder/decoder

Rotates a byte value by thirteen characters.

Caveat

The name of this package is something of a misnomer: it does not implement the traditional ROT13 substitution cipher. In that cipher, the value "13" takes on special meaning because the cipher is supposed to operate on a 26-letter alphabet (2x13); because of this, one can encode and decode using the same algorithm (it is its own inverse). In contrast, this library operates on a full byte, so its "alphabet" is 256 characters instead of 26, and thus its algorithm is not its own inverse. If you are looking for a library to perform the ROT13 Caesar cipher, this is not for you.

Command-line use

There is a simple command line interface to this library. Clone the repo and run go build cmd/rot13.go to build it.

Running rot13 -h will give you usage information:

Usage of ./rot13:
  -encode
        Encode the input string (default is to decode)
  -input string
        Input file; use '-' or leave blank to read from stdin
  -output string
        Output file; use '-' or leave blank to write to stdout

If you do not specify an input file, it will read from stdin; with no output file specified, it will print results to stdout. Some examples:

$ echo 'hello, world!' > hello
$ rot13 -encode -input hello
uryy|9-|yq.

$ rot13 -encode -input hello -output hello_encoded
$ cat hello_encoded
uryy|9-|yq.

$ ./rot13 -input hello_encoded
hello, world!

$ echo 'hello, world!' | ./rot13 -encode
uryy|9-|yq.

$ echo 'hello, world!' | ./rot13 -encode | ./rot13
hello, world!

You can also use Go's testing facility to encode and decode. Supply the input/output file path as env variables and run:

INFILE=~/.lantern/global.yaml \
  OUTFILE=~/.lantern/expanded_global.yaml \
  go test -v -run TestFunctional

Documentation

Overview

Package rot13 provides ROT13 "encryption" and "decryption".

Index

• func NewReader(wrapped io.Reader) io.Reader
• func NewWriter(wrapped io.Writer) io.Writer

Functions

func NewReader

func NewReader(wrapped io.Reader) io.Reader

NewReader creates a new io.Reader that encrypts with ROT13.

func NewWriter

func NewWriter(wrapped io.Writer) io.Writer

NewWriter creates a new io.Writer that encrypts with ROT13.