shithub: mc

ref: 04eb60944df4551eabe303b47184c0626b8a384b
dir: /libstd/wait+freebsd.myr/

use sys

use "die.use"
use "syswrap.use"

pkg std =
	type waitstatus = union
		`Wsuccess
		`Wfailure
		`Wsignal
		`Waiterror
	;;

	const wait	: (pid : pid -> waitstatus)
;;

const wait = {pid
	var st

	if sys.waitpid(pid castto(sys.pid), &st, 0) > 0
		match st & 0o177
		| 0:
			if (st >> 8) == 0
				-> `Wsuccess
			else
				-> `Wfailure
			;;
		| sig: 	-> `Wstop
		| 0x7f:-
			/* 
			when a process stops, eg, if paused by a debugger,
			wait() will return. This API is for waiting until
			a process exits. Loop instead.
			*/
			goto again
		;;
	;;
	-> `Waiterror
}