implement Send; include "sys.m";include "draw.m";include "rcxsend.m"; Send : module {	init : fn (ctxt : ref Draw->Context, argv : list of string);}; sys : Sys;rcx : RcxSend;me : int; init(nil : ref Draw->Context, argv : list of string){	sys = load Sys Sys->PATH;	me = sys->pctl(Sys->NEWPGRP, nil); 	rcx = load RcxSend "rcxsend.dis";	if (rcx == nil)		error(sys->sprint("cannot load rcx module: %r")); 	argv = tl argv;	if (len argv < 2)		error("usage: send portnum XX..."); 	portnum := int hd argv;	argv = tl argv; 	cmd := array [len argv] of byte;	for (i := 0; i < len cmd; i++) {		arg := hd argv;		argv = tl argv;		if (arg == nil || len arg > 2)			error(sys->sprint("bad arg %s\n", arg));		d1, d2 : int = 0;		d2 = hexdigit(arg[0]);		if (len arg == 2) {			d1 = d2;			d2 = hexdigit(arg[1]);		}		if (d1 == -1 || d2 == -1)			error(sys->sprint("bad arg %s\n", arg));		cmd[i] = byte ((d1 << 4) + d2);	} 	rcx->init(portnum, 1);	reply := rcx->send(cmd, len cmd, -1);	hexdump(reply);	killgrp(me);} hexdigit(h : int) : int{	if (h >= '0' && h <= '9')		return h - '0';	if (h >= 'A' && h <= 'F')		return 10 + h - 'A';	if (h >= 'a' && h <= 'f')		return 10 + h - 'a';	return -1;}		error(msg : string){	sys->print("%s\n", msg);	killgrp(me);} killgrp(pid : int){	pctl := sys->open("/prog/" + string pid + "/ctl", Sys->OWRITE);	if (pctl != nil) {		poison := array of byte "killgrp";		sys->write(pctl, poison, len poison);	}	exit;} hexdump(data : array of byte){	for (i := 0; i < len data; i++)		sys->print("%.2x ", int data[i]);	sys->print("\n");}