doc: fix tcpdump example

The expression needs to be enclosed in a single string and combined with
a logical AND to have the desired effect.

Fixes: 1188a69604c3 ("src: introduce SYNPROXY matching")
Signed-off-by: Georg Pfuetzenreuter <mail@georg-pfuetzenreuter.net>
Reviewed-by: Fernando Fernandez Mancera <fmancera@suse.de>
Signed-off-by: Florian Westphal <fw@strlen.de>

diff --git a/doc/statements.txt b/doc/statements.txt
index 6226713ba389672de88bfb94b2258c76bb604abf..834f95fbb2a8675123c1fa44c91edb9e356d6a2e 100644 (file)
--- a/doc/statements.txt
+++ b/doc/statements.txt
@@ -691,8 +691,7 @@ needed for selective acknowledgement and window scaling).
 ---------------------------------------
 Determine tcp options used by backend, from an external system
 
-              tcpdump -pni eth0 -c 1 'tcp[tcpflags] == (tcp-syn|tcp-ack)'
-                  port 80 &
+              tcpdump -pni eth0 -c 1 'tcp[tcpflags] == (tcp-syn|tcp-ack) && port 80' &
               telnet 192.0.2.42 80
               18:57:24.693307 IP 192.0.2.42.80 > 192.0.2.43.48757:
                   Flags [S.], seq 360414582, ack 788841994, win 14480,