Base64 encoding and decoding functions

1. Introduction

This module implements Base64 encoding and decoding as specified by
section 6.8 of RFC 2045.

2. Functions

2.1. Encoding

(base64-encode-vector byte-vector [output-port]) -> port/string

Encode the given BYTE-VECTOR, put the result on the OUTPUT-PORT, and
return it. If no OUTPUT-PORT is given, encoding is done in a string,
which is returned.

(base64-encode-port input-port [output-port]) -> port/string

Encode the contents of the INPUT-PORT and put the result on the
OUTPUT-PORT. If no OUTPUT-PORT is given, encoding is done in a string,
which is returned.

2.2. Decoding

(base64-decode-string string [output-port]) -> port/string

Decode the contents of the STRING, and put the result on the
OUTPUT-PORT. If no OUTPUT-PORT is given, decoding is done in a string,
which is returned.

(base64-decode-port input-port [output-port]) -> port/string

Decode the contents of the INPUT-PORT, and put the result on the
OUTPUT-PORT. If no OUTPUT-PORT is given, decoding is done in a string,
which is returned.

3. References

RFC 2045  http://www.faqs.org/rfcs/rfc2045.html