Description
MAME will record your gameplay as an MNG video file. This command will only write video so you'll need to use -wavwrite to get the audio too.
Example
mame <gamename> -mngwrite my_video.mng
Command Format
<gamename> -mngwrite <file> where <file> is the file name of the video file you want your recording done to. The example will load a game and record the gameplay as a video file called my_video.mng. The .mng is important for Windows to recognise the file format.
MAME's Default Setting
None