May 26, 2018

Encode/decode binary to printable ASCII

This is a port of btoa version 5.2, written by Paul Rutter, Joe Orost & Stefan Parmark. btoa converts 4 binary characters to 5 ascii ones, causing a 25 expansion. btoa is thus more efficient than uuencode, which causes a 33 expansion. Spaces will not be used, which should make it safe to send files over e-mail or Usenet without risking that blanks become tabs. Each resulting row of text has a single-byte checksum for error detection. A diagnosis file provides a list of errors found this way, which could then be used to retransmit only the failing lines.

Patch 1 is an unofficial, non-platform-specific patch to version 5.2 of btoa. It allows for automatic decoding of btoa files if the program is invoked as “atob” no -a argument necessary. It also outfits the Makefile to do clean and install.