diff --git a/ethermess-backend.c b/ethermess-backend.c
index baaf062..6bca040 100644
--- a/ethermess-backend.c
+++ b/ethermess-backend.c
@@ -40,9 +40,6 @@
 #define EMS_UNAVAILABLE 1
 #define EMS_OFFLINE 2
 
-unsigned const char veth0a_mac[6] = {0xb2, 0xc8, 0x5b, 0x78, 0xb4, 0xef}; //debg
-unsigned const char veth0b_mac[6] = {0xf6, 0x18, 0xfd, 0x2a, 0x80, 0xf3}; //debg
-
 bool running = true;
 
 int packet_socket;
@@ -451,28 +448,23 @@ void read_status(void) {
 }
 
 void read_command(void) {
-	int cmd = getchar();
-	if (cmd == EOF) {
-		err(1, "getchar");
-	}
-
-	unsigned const char *other_mac;
-	if (memcmp(own_mac, veth0a_mac, 6) == 0) {
-		other_mac = veth0b_mac;
-	} else {
-		other_mac = veth0a_mac;
-	}
+	unsigned char cmd;
+	readallx(0, &cmd, 1);
 
 	if (cmd == 'q') {
 		running = false;
 	} else if (cmd == 's') {
-		send_status_request(other_mac);
+		unsigned char mac[6];
+		readallx(0, mac, sizeof(mac));
+		send_status_request(mac);
 	} else if (cmd == 'i') {
-		send_msgid_request(other_mac);
+		unsigned char mac[6];
+		readallx(0, mac, sizeof(mac));
+		send_msgid_request(mac);
 	} else if (cmd == 'm') {
+		readallx(0, own_message_destination_mac, sizeof(own_message_destination_mac));
 		memcpy(own_message, "Hello, world!", 13);
 		own_message_length = 13;
-		memcpy(own_message_destination_mac, other_mac, 6);
 		own_message_send_state = QUEUED;
 	} else if (cmd == '\n') {
 		// Ignore
diff --git a/ethermess.py b/ethermess.py
index 0090101..588c43b 100644
--- a/ethermess.py
+++ b/ethermess.py
@@ -5,22 +5,51 @@ import subprocess
 import sys
 import time
 
+def writeall(f, b):
+	written = 0
+	while written < len(b):
+		written += f.write(b[written:])
+
+def parse_mac(text):
+	parts = text.split(':')
+	if len(parts) != 6:
+		raise ValueError('Invalid MAC format: %s' % text)
+
+	try:
+		parsed = bytes(int(field, 16) for field in parts)
+	except ValueError:
+		raise ValueError('Invalid MAC format %s' % text)
+
+	return parsed
+
 nick = input('nick> ').encode('utf-8')
 
-proc = subprocess.Popen(['sudo', libexec_dir + '/ethermess-backend', *sys.argv[1:]], stdin = subprocess.PIPE, stdout = sys.stdout)
+proc = subprocess.Popen(['sudo', libexec_dir + '/ethermess-backend', *sys.argv[1:]], stdin = subprocess.PIPE, stdout = sys.stdout, stderr = sys.stderr, bufsize = 0)
 
-proc.stdin.write(bytes([0, len(nick)]) + nick)
-proc.stdin.flush()
+writeall(proc.stdin, (bytes([0, len(nick)]) + nick))
 
 print('s - request status, i - request msgid, m - send message, ^D - quit')
 
 try:
 	while True:
-		proc.stdin.write(input('').encode('utf-8'))
-		proc.stdin.flush()
+		command = input('')
+
+		if command == 's':
+			mac = parse_mac(input('mac> '))
+			writeall(proc.stdin, b's' + mac)
+
+		elif command == 'i':
+			mac = parse_mac(input('mac> '))
+			writeall(proc.stdin, b'i' + mac)
+
+		elif command == 'm':
+			mac = parse_mac(input('mac> '))
+			writeall(proc.stdin, b'm' + mac)
+
+		else:
+			print('s - request status, i - request msgid, m - send message, ^D - quit')
 
 except EOFError:
-	proc.stdin.write(b'q')
-	proc.stdin.flush()
+	writeall(proc.stdin, b'q')
 
 sys.exit(proc.wait())