# MAME Path Handling

MAME has a specific order it uses when checking for user files such as ROM sets and cheat files.

## Order of Path Loading

Let's use an example of the cheat file for After Burner 2 for Sega Genesis/MegaDrive (aburner2 in the megadrive softlist), and your cheatpath is set to "cheat" (as per the default) -- this is how MAME will search for that cheat file:

1. `cheat/megadriv/aburner2.xml`

2. `cheat/megadriv.zip` -> `aburner2.xml` Notice that it checks for a .ZIP file first before a .7Z file.

3. `cheat/megadriv.zip` -> `<arbitrary path>/aburner2.xml` It will look for the first (if any) `aburner2.xml` file it can find inside that zip, no matter what the path is.

4. `cheat.zip` -> `megadriv/aburner2.xml` Now it is specifically looking for the file and folder combination, but inside the cheat.zip file.

5. `cheat.zip` -> `<arbitrary path>/megadriv/aburner2.xml` Like before, except looking for the first (if any) `aburner2.xml` inside a `megadriv` folder inside the zip.

6. `cheat/megadriv.7z` -> `aburner2.xml` Now we start checking 7ZIP files.

7. `cheat/megadriv.7z` -> `<arbitrary path>/aburner2.xml`

8. `cheat.7z` -> `megadriv/aburner2.xml`

9. `cheat.7z` -> `<arbitrary path>/megadriv/aburner2.xml` Similar to zip, except now 7ZIP files.

[todo: ROM set loading is slightly more complicated, adding CRC. Get that documented in the next day or two.]