Initial import

discardd.c

@@ -0,0 +1,59 @@
+/*
+ * discard
+ * Written in 2020 by Lucas
+ * CC0 1.0 Universal/Public domain - No rights reserved
+ *
+ * To the extent possible under law, the author(s) have dedicated all
+ * copyright and related and neighboring rights to this software to the
+ * public domain worldwide. This software is distributed without any
+ * warranty. You should have received a copy of the CC0 Public Domain
+ * Dedication along with this software. If not, see
+ * <http://creativecommons.org/publicdomain/zero/1.0/>.
+ */
+
+#include <err.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+static void
+usage(void)
+{
+	fprintf(stderr, "Usage: %s -t | -u\n", getprogname());
+	exit(1);
+}
+
+int
+main(int argc, char *argv[])
+{
+	int ch, do_tcp, do_udp;
+
+	do_tcp = do_udp = 0;
+	while ((ch = getopt(argc, argv, "tu")) != -1) {
+		switch (ch) {
+		case 't':
+			do_tcp = 1;
+			break;
+		case 'u':
+			do_udp = 1;
+			break;
+		default:
+			usage();
+		}
+	}
+	argc -= optind;
+	argv += optind;
+
+	if (argc > 0)
+		usage();
+	if (!do_tcp && !do_udp)
+		errx(1, "one of -t or -u is needed");
+	if (do_tcp && do_udp)
+		errx(1, "-t and -u are mutually exclusive");
+	if (do_udp)
+		errx(1, "UDP unimplemented");
+	if (do_tcp)
+		errx(1, "TCP unimplemented");
+
+	return 0;
+}