ref: d5821ae5517a14a33d59b742f544e7de7afd238f
dir: /sys/src/libc/9sys/waitpid.c/
#include <u.h>
#include <libc.h>
#include <fcall.h>
int
waitpid(void)
{
	int n;
	char buf[512], *fld[5];
	n = await(buf, sizeof buf-1);
	if(n <= 0)
		return -1;
	buf[n] = '\0';
	if(tokenize(buf, fld, nelem(fld)) != nelem(fld)){
		werrstr("couldn't parse wait message");
		return -1;
	}
	return atoi(fld[0]);
}