implement Announce;include "sys.m";	sys:	Sys;include "grid/announce.m"; init(){	sys = load Sys Sys->PATH;} announce(): (string, ref Sys->Connection){	sysname := readfile("/dev/sysname");	(ok, c) := sys->announce("tcp!*!0");	if(ok == -1)		return (nil, nil);	local := readfile(c.dir + "/local");	if(local == nil)		return (nil, nil);	for(i := len local - 1; i >= 0; i--)		if(local[i] == '!')			break;	port := local[i+1:];	if(port == nil)		return (nil, nil);	if(port[len port - 1] == '\n')		port = port[0:len port - 1];	return ("tcp!" + sysname + "!" + port, ref c);}  readfile(f: string): string{	fd := sys->open(f, Sys->OREAD);	if (fd == nil)		return nil;	buf := array[8192] of byte;	n := sys->read(fd, buf, len buf);	if (n <= 0)		return nil;	return string buf[0:n];}