Support M3U files with Dolphin

Any chance we could support M3U files with GameCube and Wii games on Dolphin? Dolphin has an automatic disc change option (that is actually enabled on the standalone already) but it doesn't work if you pass the iso via the command line. If you have multiple discs and you are loading it via the command line either you have to pass the -e parameter for each iso (which probably won't necessarily work well with ES) or pass a M3U file which it will support. I loaded the Dolphin emulator in the pack directly and verified that automatic disc change does work with a M3U at least from the GUI.

Hello
Have you try, with BatGui, to add .m3u to the extension list available for this system ?

I actually created an override es_systems_gamecube.cfg file and added it that way. Frontend recognizes it properly and adds the extension into the list but when you try to launch it just flashes a box then bails. I do wonder if the helper app is passing the correct options to dolphin...

why you don't use the Dolphin core?

It actually locks up for me under RetroBat. Weirdly it works fine in my standalone install but that is a different version.

EDIT: I'd just like to see it work under standalone dolphin.  I'm doing some testing and currently the dolphin included and the one that I updated to (using dolphin's updater) neither work if I try it from the commandline directly.  No errors or anything.  If I check it using my other copy though it throws and error and says it couldn't find the images so I'm looking further.  I may have to adapt how the m3u files are built.

EDIT: So, this issue is 2-fold.
1) Normally when m3u files are assembled they just contain the files in the list.  When I build them, it is literally just the filename.  No path.  When dolphin launches it checks where it launched from (the working directory) then checks the root of the current drive (I'm guessing here).  When the error pops for me on my separate copy it just has the drive letter followed by the game entry.  If I start from within the folder where the files exist it loads it up just fine without error.  

2) Currently EmulationStation has the working directory as where the standalone emulator is at and not the game roms folder and I'm not seeing a way to change that although I'm researching it.

EDIT (sorry. last edit here...): So, it works if I set the rom entry in the m3u relative to drive root. It doesn't have to include the drive letter itself. So \RetroBat\roms\gamecube\image.iso works fine. Don't think ES or RetroBat should have to change behavior or handling on this so I'm posting over on the Dolphin forum. If anything, it should be checking existing library paths already defined.