This document describes the organization of the various source files MAME and MESS use.

• makefile – Makefile for MAME
• makefile.mes – Makefile for MESS
• makefile.sdl – Makefile for SDLMAME/SDLMESS
• docs/ – Documentation
• src/ – Source code
  • emu/ – generic emulation files
    • cpu/ – CPU cores
    • sound/ – sound cores
    • debug/ – debugger code
    • audio/ – generic audio files
    • layout/ – generic layout files
    • machine/ – generic machine files
    • video/ – generic video files
  • mame/ – MAME-specific files
    • drivers/ – drivers
    • includes/ – includes
    • layout/ – layouts
    • machine/ – generic hardware
    • audio/ – sound hardware
    • video/ – video hardware
    • etc/ – misc files
  • mess/ – MESS-specific files
    • audio/ – audio hardware
    • devices/ – devices descriptions
    • drivers/ – drivers
    • formats/ – cassette and disk formats
    • includes/ – include files
    • layout/ – layouts
    • machine/ – generic emulations
    • osd/ – OS-dependent code
      • sdl/ – for the SDL port
      • windows/ – for the Windows versions
    • tests/ – XML test descriptions for MESSTest
    • tools/ – MESS-specific tools
      • dat2html/ – Converts sysinfo.dat to HTML files
      • imgtool/ – Can read and write files from various image formats
      • messdocs/ – Used to create mess.chm
      • messtest/ – Regression test tool
    • video/ – video hardware
  • lib/ – libraries
    • util/ – various files
    • zlib/ – zlib library
    • expat/ – expat library
  • osd/ – OS-dependent code
    • osdmini/ – mini OS-dependent code
    • sdl/ – SDL OS-dependent code
    • windows/ – Windows OS-dependent code
  • tools/ – misc tools