ref: 2c4ac1330705a7358cd9946ac5af3308ba1cef23
dir: /lib/thread/spawn+plan9.myr/
use std use sys pkg thread = type tid = uint64 const spawn : (fn : (-> void) -> std.result(tid, byte[:])) ;; const spawn = {fn match sys.rfork(sys.Rfproc | sys.Rfmem | sys.Rfnowait) | 0: fn() std.exit(0) | -1: -> `std.Fail "unable to spawn thread" | thr: -> `std.Ok thr castto(tid) ;; }