This patch adds a cvar com_pipefile that specifies a filename at which to create a named FIFO pipe while the game is running. This allows other processes/scripts/bots to easily and conveniently send commands to the running server, which otherwise can only be done quite hackishly via either netcat->rcon or screen. By comparison, this patch allows control as easily as:

echo cp The server is shutting down for maintenance > .ioq3ded_pipe
echo quit > .ioq3ded_pipe

The option is nonfunctional on Windows because the closest Windows equivalent to this functionality at the OS level appears to be rather different and not particularly useful for this purpose anyway. Tested extensively in Linux. Verified that it at least does nothing in Windows. It should work fine in other nix-like OS's but I could not test them.