fprintf(stderr, "Insufficient number of arguments.\n");
mainusage();
main(int argc, char *argv[]){    if (argc < 2)    {	fprintf(stderr, "Insufficient number of arguments.\n");	exit(-1);    }    if (!strcmp(argv[1], "sign"))      keynote_sign(argc - 1, argv + 1);    else      if (!strcmp(argv[1], "verify"))	keynote_verify(argc - 1, argv + 1);      else	if (!strcmp(argv[1], "sigver"))	  keynote_sigver(argc - 1, argv + 1);	else	  if (!strcmp(argv[1], "keygen"))	    keynote_keygen(argc - 1, argv + 1);    fprintf(stderr, "Usage:\n");    fprintf(stderr, "\tsign ...\n");    fprintf(stderr, "\tsigver ...\n");    fprintf(stderr, "\tverify ...\n");    fprintf(stderr, "\tkeygen ...\n");    exit(-1);}