#include <u.h>#include <libc.h> static Lock tlock; longtime(long *tp){	char b[20];	static int f = -1;	long t; 	lock(&tlock);	memset(b, 0, sizeof(b));	f = open("/dev/time", OREAD|OCEXEC);	if(f >= 0) {		seek(f, 0, 0);		read(f, b, sizeof(b));	}	t = atol(b);	if(tp)		*tp = t;	unlock(&tlock); 	return t;}