Grepping grep output fails
- by viraptor
I'm trying to grep the output of ngrep. Unfortunately when I add another grep to the pipeline, I get no output at all. It can be some other command too - cat / grep / tee - everything breaks the chain. Example:
# this works:
$ ngrep -l -q -T -Wbyline -d any udp and port 5060 |
egrep -B1 '^SIP/2.0 180'
--
U +1.469535 xxx:5060 -> xxx:5060…