Maybe you’re misremembering or referring to Doom (2016). The original Doom was developed for DOS and id had to build a lot of its own network stack. BSD style

Maybe you’re misremembering or referring to Doom (2016). The original Doom was developed for DOS and id had to build a lot of its own network stack. BSD style socket based networking wasn’t a given in DOS. Still, zclaw is an impressive achievement.