#include "compose.h" voidusage(void){	fprint(2, "usage: compose [-t] [-c chan] [-o drawop] img ...\n");	exits("usage");} voidmain(int argc, char **argv){	int i;	ulong chan, op;	C *c; 	chan = 0;	op = SoverD;	ARGBEGIN{	case 'c':		chan = strtochan(EARGF(usage()));		if(chan == 0)			usage();		break;	case 'o':		op = strtoop(EARGF(usage()));		if(op == ~0)			usage();		break;	case 't':		flag['t'] = 1;		break;	default:		usage();	}ARGEND	if(argc == 0)		usage();	c = malloc(argc*sizeof *c);	if(c == nil)		sysfatal("malloc: %r");	for(i = 0; i < argc; i++)		intimg(c + i, argv[i], -1);	composer(c, argc, chan, op);	exits("");}