Have an ingame menu with the command "echo "new_id:$ID$"; condump idchanged; wait; wait; ...; wait; menu result"
Make your program run in the background permanently and poll the condump file. Whenever it changes, get the ID's names and write it to the menu file "result" which will be loaded by the game.
But seriously, don't do that. What you did there is nice and other people already did that before with external applications, but if you want a command to be available ingame, grab the source and add the ingame command. The chain should work this way:
client requests data from server -> server answers with machine readable data -> client generates user friendly data -> client displays it (low server load, medium client load, low network load)
not this way:
client puts his request on the harddrive -> polling application requests data from server -> server generates user friendly data --> application parses and extracts only parts of that -> application puts result on harddrive -> client who started polling the moment he issued the request (or who had a race condition) reads the data and displays it. (high harddrive activity, high client load, high server load, high network load)
