M4

M4 (an acronym for Macro - M and 4 more letters) is a general-purpose macro language processor.

History
The predecessor macro processor m3 was written by Dennis Ritchie for the AP-3 minicomputer.

M4 was originally written by Brian Kernighan and Dennis Ritchie in 1977.

Implementations

 * The Heirloom Development Tools
 * GNU M4 - used by GNU Autoconf
 * BSD m4

Links

 * Michael Breen: Notes on the M4 Macro Language