How to filter wvdial/pppd terminal output

Question

I use wvdial to connect to the net with with my USB modem. It works correctly, and I am quite happy with it. When I start it in XFCE I have it set to output to a borderless, transparent terminal so the status displays on my desktop, life is good. Everything is great, I just want to tweak it.

I'm hoping to filter the output with a 'grep -v' to remove unsightly non-information. Here is the output from a sample run. The output is consistantly the same, except for IP addresses..

--> WvDial: Internet dialer version 1.60
--> Cannot get information for serial port.
--> Initializing modem.
--> Sending: ATZ
ATZ
OK
--> Sending: ATQ0 V1 E1 S0=0 &C1 &D2 +FCLASS=0
ATQ0 V1 E1 S0=0 &C1 &D2 +FCLASS=0
OK
--> Modem initialized.
--> Sending: ATDT#777
--> Waiting for carrier.
ATDT#777
CONNECT
--> Carrier detected.  Waiting for prompt.
~[7f]}#@!}!}!} }9}"}&} } } } }#}%B#}%}%}&3za[02]}'}"}(}"J};~
--> PPP negotiation detected.
--> Starting pppd at Mon Nov 14 11:00:06 2011
--> Warning: Could not modify /etc/ppp/pap-secrets: Permission denied
--> --> PAP (Password Authentication Protocol) may be flaky.
--> Warning: Could not modify /etc/ppp/chap-secrets: Permission denied
--> --> CHAP (Challenge Handshake) may be flaky.
--> Pid of pppd: 17776
--> Using interface ppp0
--> pppd: >[7f]
--> pppd: >[7f]
--> pppd: >[7f]
--> pppd: >[7f]
--> local  IP address 10.81.25.50
--> pppd: >[7f]
--> remote IP address 10.133.28.10
--> pppd: >[7f]
--> primary   DNS address 10.133.20.11
--> pppd: >[7f]
--> secondary DNS address 10.132.20.11
--> pppd: >[7f]
^CCaught signal 2:  Attempting to exit gracefully...
--> Terminating on signal 15
--> pppd: >[7f]
--> Connect time 0.2 minutes.
--> pppd: >[7f]
--> pppd: >[7f]
--> Disconnecting at Mon Nov 14 11:00:16 2011

Can someone please help me with a command line or script that would filter that output and remove the --> pppd: >[7f] lines, and possibly the pap/chap warnings(they're bogus).

I've tried several things, with pipes and redirection to grep but haven't hit on anything that seems to effect the output. As a note: in the pppd:/[7f] lines it appears the second '>' character could be just about anything(still don't know what pppd is trying to tell me. :)

Thanks!

EDIT: I got it. Simple stuff really, if you're not a knob. I'm a knob..

wvdial 2>&1 | grep -v -i -E "7f]|pap|chap"

the output is on stderr and pipes are for stdout. the 2>&1 redirects so it will pipe properly.

If you've read this far, thanks.

score 2 · Accepted Answer · edited Apr 13 '17 at 12:36

What I would do is to redirect the output of wvdial to a file, and separately print out “interesting” lines from the file as they appear.

wvdial >wvdial.log 2>&1

Here's one way to filter the file. tail -n +1 -f means to follow the file as it grows (-f), starting with the first line (-n +1). The filter grep -v means to display all but the matching line; -E chooses the “modern” syntax for regular expressions.

tail -n +1 -f wvdial.log |
grep -vE '^--> (pppd: >\[7f\]|Warning)$'

There are several programs that combine the file watch feature of tail -f (which is often called tailing a file) with filtering and coloring capabilities; browse the tail tag on this site and see in particular grep and tail -f? and How to have tail -f show colored output.

What I've settled on, is redirect to a log file so I capture all output. Then tail -f, piped through grep -v, piped through sed to colorize. I looked at multitail for colorizing, but it looks like it has a learning curve of its own. If I've gotta learn something, at this point it should be regex and the standard tools. :) Thanks for your input! — BentFX, Nov 16 '11 at 06:12

How to filter wvdial/pppd terminal output

1 Answers1