--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/sip-manual-out/disc_cmd.c	Thu Sep 29 17:21:11 2022 -0800
@@ -0,0 +1,76 @@
+/*
+ * In this module we implement user-driven sending of CANCEL and BYE
+ * disconnection requests.
+ */
+
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <strings.h>
+#include "../libsip/out_msg.h"
+
+extern struct sockaddr_in sip_dest_sin;
+extern char to_uri[];
+
+send_cancel_req()
+{
+	struct sip_msg_out msg;
+	int rc;
+
+	rc = start_request_out_msg(&msg, "CANCEL", to_uri);
+	if (rc < 0) {
+msg_size_err:	fprintf(stderr, "composing CANCEL message: size error\n");
+		return(-1);
+	}
+	rc = add_req_boilerplate(&msg, "1 CANCEL", 0);
+	if (rc < 0)
+		goto msg_size_err;
+	out_msg_finish(&msg);
+	sip_tx_packet(&msg, &sip_dest_sin);
+	return(0);
+}
+
+send_bye_req()
+{
+	struct sip_msg_out msg;
+	int rc;
+
+	rc = start_request_out_msg(&msg, "BYE", to_uri);
+	if (rc < 0) {
+msg_size_err:	fprintf(stderr, "composing BYE message: size error\n");
+		return(-1);
+	}
+	rc = add_req_boilerplate(&msg, "2 BYE", 1);
+	if (rc < 0)
+		goto msg_size_err;
+	out_msg_finish(&msg);
+	sip_tx_packet(&msg, &sip_dest_sin);
+	return(0);
+}
+
+void
+select_stdin()
+{
+	char buf[256], *cp;
+
+	fgets(buf, sizeof buf, stdin);
+	cp = index(buf, '\n');
+	if (cp) {
+		while (cp > buf && isspace(cp[-1]))
+			cp--;
+		*cp = '\0';
+	}
+	for (cp = buf; isspace(*cp); cp++)
+		;
+	if (!*cp)
+		return;
+	if (!strcmp(cp, "b") || !strcasecmp(cp, "bye"))
+		send_bye_req();
+	else if (!strcmp(cp, "c") || !strcasecmp(cp, "cancel"))
+		send_cancel_req();
+	else
+		fprintf(stderr, "error: non-understood stdin command\n");
+}