Revival of the 1973 Unix speak program

This repository contains the source code of Unix speak program that appeared in the Third (1973) to Sixth (1975) Research Unix editions, slightly adjusted to run on a modern computer. Details on the code's provenance and the methods employed for reviving it can be found in this blog post.

Repository contents

1970s code

• speak.c: Original source code adjusted to run on modern computers; commits detail the modifications made
• speak.v: Speech rules

Modern additions

• Makefile: Code and rule compilation
• votrax-espeak.md: Map between Votrax, speak, and espeak phoneme codes
• votrax-mnemonics.sed: Convert speak output into Votrax mnemonics to help debugging
• votrax-espeak.sed: Convert speak output into espeak-ng phonemes
• Caldera-license.pdf: Early Unix source code license terms

Build

Run make on a system with a C compiler and make.

Run

On a system containing the espeak command, run:

echo Hello world |
speak speak.m |
LC_ALL=C ./votrax-espeak.sed |
espeak

Ports to other languages

• Rust

Contribute

Improvements to the phoneme map as well as bug fixes that retain the historical accuracy of the speak and rules source code are welcomed through GitHub pull requests.