pub fn steam_app(block: &[u16]) -> Option<u32>Expand description
The Steam app id in a NAME=value\0...\0\0 block, the value of
STEAM_APP_VAR. A value that is empty, 0 or no number is no app id:
Steam’s own processes have the variable empty.
It has to come from the Windows block: Wine does not copy that to the unix
environment, so getenv does not see what Steam sets for a game.