00README.TXT  
RZSZ9305.TAR   An implementation of the XMODEM, YMODEM, and ZMODEM protocols, written in C.  From the original author. Contributor: Chuck Forsberg <caf@omen.uucp>
UMODEM.TAR     An implementation of the XMODEM, TERM II File Transfer Protocol #1, and TERM II File Transfer Protocol #4.  This version runs under several versions of UNIX. Contributor: Dave Curry <davy@erg.sri.com>
XMODEM31.TAR   An implementation of the Christiansen (XMODEM) file transfer protocol. This implementation works only under 4.2/4.3BSD. Version 3.10.