#include <u.h>#include <libc.h> char*get9root(void){	static char *s; 	if(s)		return s; 	if((s = getenv("PF9")) != 0)		return s;	if((s = getenv("PLAN9")) != 0)		return s;	/* could do better - search $PATH */	s = "/usr/local/plan9";	return s;}