FCEUX provides a LUA 5.1 engine that allows for in-game scripting capabilities. LUA is enabled either way. It is just a matter of whether LUA is statically linked internally or dynamically linked to a system library.
You should be able to run most of the scripts in this directory out of the box. However, some of the the lua scripts require functionality from the "auxlib.lua" library. This file can be copied from "./bin/auxlib.lua" or "./src/auxlib.lua". You will need to place this file in the LUA library search path if a script bombs out looking for auxlib.lua. If the script bombs out, the console output will let you know what the search path are (/usr/local/lib/lua/5.1/ on my particular system). You can simply copy the auxlib to a preferred location to utilize the functions in the auxiliary lua library.
In addition, some of the lua scripts require functionality from the "iup" GUI library. You can obtain binaries and source for "iup" upstream (http://www.tecgraf.puc-rio.br/iup/), but I would recommend obtaining packages from your Linux distribution if you are able, as it can be difficult to compile or get the binaries working correctly on a given system.
You will need to add the location that the libiup*.so files to the LUA_CPATH. This can be done with the following command (please note that the location where iup is installed with vary based on how you installed iup):
For example, if libiuplua51.so is located in '/usr/lib', you can run the following command before executing fceux to place the library in the search path:
Finally, if any scripts complaints about "attempt to index global 'iup' (a nil value)", this means that "iup" needs to be explicitly loaded into the script. You can add the following line to the head of script to manually load "iup":
* A. First of all, for the best sound quality be sure you are using SDL 1.2.14 or later. Versions 1.2.13 and earlier are known to have problems with fceux! Next, try different SDL audio drivers to see if this makes any difference. You can do this by using this command before running fceux:
where driver is either: 'pulse' for pulseaudio;' alsa' for ALSA; 'dsp' for OSS; 'esd' for ESD; see SDL documentation for details (http://www.libsdl.org/docs/html/sdlenvvars.html)
If you have an issue with fceux, report it in the github bug tracker (see fceux at github.com). If you would like to contact the author of this readme personally, e-mail LTsmooth42 <at> gmail <dot> com. You can also check us out at #fceu on irc.freenode.net.