implement Uuencode; include "sys.m";	sys : Sys;include "draw.m"; Uuencode : module{	init : fn(nil : ref Draw->Context, argv : list of string);}; fatal(s : string){	sys->fprint(sys->fildes(2), "%s\n", s);	exit;} usage(){	fatal("usage: uuencode [ sourcefile ] remotefile");} init(nil : ref Draw->Context, argv : list of string){	fd : ref Sys->FD;	mode : int; 	sys = load Sys Sys->PATH;	argv = tl argv;	if (argv == nil)		usage();	if (tl argv != nil) {		fd = sys->open(hd argv, Sys->OREAD);		if (fd == nil)			fatal(sys->sprint("cannot open %s", hd argv));		(ok, d) := sys->fstat(fd);		if (ok < 0)			fatal(sys->sprint("cannot stat %s: %r", hd argv));		if (d.mode & Sys->DMDIR)			fatal("cannot uuencode a directory");		mode = d.mode;		argv = tl argv;	}	else {		fd = sys->fildes(0);		mode = 8r666;	}	if (tl argv != nil)		usage();	sys->print("begin %o %s\n", mode, hd argv);	encode(fd);	sys->print("end\n");} LEN : con 45; code(c : int) : byte{	return byte ((c&16r3f) + ' ');} encode(ifd : ref Sys->FD){	c, d, e : int; 	ofd := sys->fildes(1);	ib := array[LEN] of byte;	ob := array[4*LEN/3 + 2] of byte;	for (;;) {		n := sys->read(ifd, ib, LEN);		if (n < 0)			fatal("cannot read input file: %r");		if (n == 0)			break;		i := 0;		ob[i++] = code(n);		for (j := 0; j < n; j += 3) {			c = int ib[j];			ob[i++] = code((0<<6)&16r00 | (c>>2)&16r3f);			if (j+1 < n)				d = int ib[j+1];			else				d = 0;			ob[i++] = code((c<<4)&16r30 | (d>>4)&16r0f);			if (j+2 < n)				e = int ib[j+2];			else				e = 0;			ob[i++] = code((d<<2)&16r3c | (e>>6)&16r03);			ob[i++] = code((e<<0)&16r3f | (0>>8)&16r00);		}		ob[i++] = byte '\n';		if (sys->write(ofd, ob, i) != i)			fatal("bad write to output: %r");	}	ob[0] = code(0);	ob[1] = byte '\n';	if (sys->write(ofd, ob, 2) != 2)		fatal("bad write to output: %r");}