Once your program is compiled, it needs to be downloaded to the RCX brick. The firmdl utility that comes with legOS is the tool that is used. The brick has to be in the "accept firmware" state. On initial powerup (after having no batteries) the brick is in this state and will beep on powerup. If a legOS program is currently in memory, the brick can be placed into this state by turning on the brick, holding down the "Prgm" button and pressing the "On-Off" switch.

To download a *.srec file: 

export RCXTTY=/dev/cua2   # or whatever port the IR tower is on
/usr/local/mindstorms/bin/firmdl avoid.srec

There is a new version of firmdl at http://graphics.stanford.edu/~kekoa/rcx/tools.html#Firmdl that offers 4x faster downloads. The first step is to reset the brick as above and then using firmdl in "slow" mode download a small code fragment to the brick (fastdl.srec) and then download the main program with firmdl on 4x speed: 

$ firmdl3 --slow fastdl.srec 
$ firmdl3 avoid.srec
Previous - Building the SREC Files Main Next - Programming Model
Monty Stein Dec 18, 1999
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