How to set an environment variable for an specific game on Steam for Linux?

Well, how? There is that "SET LAUNCH OPTIONS" button, but I believe that is only fit to command line switches.

steam

— lvella
fonte

It is possible to prefix the command with your environment variable in the set launch options like so:

YOUR_VARIABLE=1 %command%

— Aldrik
fonte

Does this still work? The linked docs don't mention it.

— Jeroen

It really works according to /proc/<game pid>/environ.

— and

Is there a way to do this with multiple options? Would separating them with semicolons work?

— Robert Wm Ruedisueli

You just leave a space, so my current one is mesa_glthread=true R600_DEBUG=sbcl,hyperz,llvm,sisched,forcedma vblank_mode=0 %command%.

— pbhj