diff --git a/cangw.c b/cangw.c
index a6b1697..af4d862 100644
--- a/cangw.c
+++ b/cangw.c
@@ -225,39 +225,39 @@ void print_usage(char *prg)
 	fprintf(stderr, "%s - manage PF_CAN netlink gateway.\n", prg);
 	fprintf(stderr, "\nUsage: %s [options]\n\n", prg);
 	fprintf(stderr, "Commands:\n");
-	fprintf(stderr, "           -A  (add a new rule)\n");
-	fprintf(stderr, "           -D  (delete a rule)\n");
-	fprintf(stderr, "           -F  (flush / delete all rules)\n");
-	fprintf(stderr, "           -L  (list all rules)\n");
+	fprintf(stderr, "          -A  (add a new rule)\n");
+	fprintf(stderr, "          -D  (delete a rule)\n");
+	fprintf(stderr, "          -F  (flush / delete all rules)\n");
+	fprintf(stderr, "          -L  (list all rules)\n");
 	fprintf(stderr, "Mandatory:\n");
-	fprintf(stderr, "           -s <src_dev>  (source netdevice)\n");
-	fprintf(stderr, "           -d <dst_dev>  (destination netdevice)\n");
+	fprintf(stderr, "          -s <src_dev>  (source netdevice)\n");
+	fprintf(stderr, "          -d <dst_dev>  (destination netdevice)\n");
 	fprintf(stderr, "Options:\n");
-	fprintf(stderr, "           -X  (this is a CAN FD rule)\n");
-	fprintf(stderr, "           -t  (preserve src_dev rx timestamp)\n");
-	fprintf(stderr, "           -e  (echo sent frames - recommended on vcanx)\n");
-	fprintf(stderr, "           -i  (allow to route to incoming interface)\n");
-	fprintf(stderr, "           -u <uid>  (user defined modification identifier)\n");
-	fprintf(stderr, "           -l <hops>  (limit the number of frame hops / routings)\n");
-	fprintf(stderr, "           -f <filter>  (set CAN filter)\n");
-	fprintf(stderr, "           -m <mod>  (set Classic CAN frame modifications)\n");
-	fprintf(stderr, "           -M <MOD>  (set CAN FD frame modifications)\n");
-	fprintf(stderr, "           -x <from_idx>:<to_idx>:<result_idx>:<init_xor_val>  (XOR checksum)\n");
-	fprintf(stderr, "           -c <from>:<to>:<result>:<init_val>:<xor_val>:<crctab[256]>  (CRC8 cs)\n");
-	fprintf(stderr, "           -p <profile>:[<profile_data>]  (CRC8 checksum profile & parameters)\n");
+	fprintf(stderr, "          -X  (this is a CAN FD rule)\n");
+	fprintf(stderr, "          -t  (preserve src_dev rx timestamp)\n");
+	fprintf(stderr, "          -e  (echo sent frames - recommended on vcanx)\n");
+	fprintf(stderr, "          -i  (allow to route to incoming interface)\n");
+	fprintf(stderr, "          -u <uid>  (user defined modification identifier)\n");
+	fprintf(stderr, "          -l <hops>  (limit the number of frame hops / routings)\n");
+	fprintf(stderr, "          -f <filter>  (set CAN filter)\n");
+	fprintf(stderr, "          -m <mod>  (set Classic CAN frame modifications)\n");
+	fprintf(stderr, "          -M <MOD>  (set CAN FD frame modifications)\n");
+	fprintf(stderr, "          -x <from_idx>:<to_idx>:<result_idx>:<init_xor_val>  (XOR checksum)\n");
+	fprintf(stderr, "          -c <from>:<to>:<result>:<init_val>:<xor_val>:<crctab[256]>  (CRC8 cs)\n");
+	fprintf(stderr, "          -p <profile>:[<profile_data>]  (CRC8 checksum profile & parameters)\n");
 	fprintf(stderr, "\nValues are given and expected in hexadecimal values. Leading 0s can be omitted.\n");
 	fprintf(stderr, "\n");
 	fprintf(stderr, "<filter> is a <value><mask> CAN identifier filter:\n");
-	fprintf(stderr, "   <can_id>:<can_mask>\t(matches when <received_can_id> & mask == can_id & mask)\n");
-	fprintf(stderr, "   <can_id>~<can_mask>\t(matches when <received_can_id> & mask != can_id & mask)\n");
+	fprintf(stderr, "  <can_id>:<can_mask>  (matches when <received_can_id> & mask == can_id & mask)\n");
+	fprintf(stderr, "  <can_id>~<can_mask>  (matches when <received_can_id> & mask != can_id & mask)\n");
 	fprintf(stderr, "\n");
 	fprintf(stderr, "<mod> is a CAN frame modification instruction consisting of\n");
 	fprintf(stderr, "<instruction>:<can_frame-elements>:<can_id>.<can_dlc>.<can_data>\n");
-	fprintf(stderr, "   <instruction>  is one of 'AND' 'OR' 'XOR' 'SET'\n");
-	fprintf(stderr, "   <can_frame-elements>  is _one_ or _more_ of 'I'dentifier 'L'ength 'D'ata\n");
-	fprintf(stderr, "   <can_id>  is an u32 value containing the CAN Identifier\n");
-	fprintf(stderr, "   <can_dlc>  is an u8 value containing the data length code (0 .. 8)\n");
-	fprintf(stderr, "   <can_data>  is always eight(!) u8 values containing the CAN frames data\n");
+	fprintf(stderr, "  <instruction>  is one of 'AND' 'OR' 'XOR' 'SET'\n");
+	fprintf(stderr, "  <can_frame-elements>  is _one_ or _more_ of 'I'dentifier 'L'ength 'D'ata\n");
+	fprintf(stderr, "  <can_id>  is an u32 value containing the CAN Identifier\n");
+	fprintf(stderr, "  <can_dlc>  is an u8 value containing the data length code (0 .. 8)\n");
+	fprintf(stderr, "  <can_data>  is always eight(!) u8 values containing the CAN frames data\n");
 	fprintf(stderr, "\n");
 	fprintf(stderr, "<MOD> is a CAN FD frame modification instruction consisting of\n");
 	fprintf(stderr, "<instruction>:<canfd_frame-elements>:<can_id>.<flags>.<len>.<can_data>\n");
@@ -270,9 +270,9 @@ void print_usage(char *prg)
 	fprintf(stderr, "The max. four modifications are performed in the order AND -> OR -> XOR -> SET\n");
 	fprintf(stderr, "\n");
 	fprintf(stderr, "Supported CRC 8 profiles:\n");
-	fprintf(stderr, " Profile '%d' (1U8)        - add one additional u8 value\n", CGW_CRC8PRF_1U8);
-	fprintf(stderr, " Profile '%d' (16U8)       - add u8 value from table[16] indexed by (data[1] & 0xF)\n", CGW_CRC8PRF_16U8);
-	fprintf(stderr, " Profile '%d' (SFFID_XOR)  - add u8 value (can_id & 0xFF) ^ (can_id >> 8 & 0xFF)\n", CGW_CRC8PRF_SFFID_XOR);
+	fprintf(stderr, " Profile '%d' (1U8)        add one additional u8 value\n", CGW_CRC8PRF_1U8);
+	fprintf(stderr, " Profile '%d' (16U8)       add u8 value from table[16] indexed by (data[1] & 0xF)\n", CGW_CRC8PRF_16U8);
+	fprintf(stderr, " Profile '%d' (SFFID_XOR)  add u8 value (can_id & 0xFF) ^ (can_id >> 8 & 0xFF)\n", CGW_CRC8PRF_SFFID_XOR);
 	fprintf(stderr, "\n");
 	fprintf(stderr, "Examples:\n");
 	fprintf(stderr, "%s -A -s can0 -d vcan3 -e -f 123:C00007FF -m SET:IL:333.4.1122334455667788\n", prg);