Carmack shares the current opinion of many that you can’t really make a good business case for supporting Linux with mainstream games; and despite the unofficial binaries that id used to release, Zenimax has no such policy. In addition, Zenimax has never published any Linux titles and partners with Aspyr for the release of Mac version of Zenimax titles.
While Carmack has championed the continued tradition of releasing id source code, that is also apparently up in the air at this time. He will continue to push internally for the release of the source code; but he isn’t pushing for Linux ports, despite the work that Valve is doing in this area with a Linux release of Steam.
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