ref: 83ac0784c67f15c98b62cdacc660be63c447474a
dir: /lib/std/wait+posixy.myr/
use sys use "die" use "syswrap" pkg std = type waitstatus = union `Wsuccess `Wfailure `Wsignalled `Waiterror ;; const wait : (pid : pid -> waitstatus) const waitany : (-> (pid, waitstatus)) ;; const waitany = { match dowait(-1) | (p, st): -> ((p : pid), st) ;; } const wait = {pid match dowait(pid) | (_, st): -> st ;; } const dowait = {pid var st, p :again p = sys.waitpid((pid : sys.pid), &st, 0) if p > 0 match sys.waitstatus(st) /* when a process stops, eg, if paused by a debugger, wait() will return. This API is for waiting until a process exits. Loop instead. */ | `sys.Waitstop sig: goto again | `sys.Waitfail fail: -> (p, `Waiterror) | `sys.Waitsig sig: -> (p, `Wsignalled) | `sys.Waitexit 0: -> (p, `Wsuccess) | `sys.Waitexit _: -> (p, `Wfailure) ;; ;; -> (-1, `Waiterror) }