Filter piped stream with sed or grep 1821

On 7 Jul 2006, in the Usenet newsgroup comp.os.linux.misc, in article

OK - you might be surprised of the number of 'show me how to spy on network use, email, what-ever' get posted to security groups with no understanding of the laws that may be involved.

Not at all - we've had that policy since the late 1980s. There are several computers in the break areas that are not connected to our net (we're an R&D facility) that are expressly for employee use to surf, check mail, or as in my case, ssh into my home network.

Don't know what the addresses are on your setup, but '192.168.1.10' is satisfied with '192.168.1.10' and '192.168.1.100-9' etc. Normally when I run into a problem like this, I would change the string to select (rather than reject) a term, to see when it is finding. Thus

urlsnarf -i eth0 -n grep 192.168.1.10 and make any adjustments required. Invariably, it's a "duh" error.

urlsnarf -i eth0 -n egrep -v '192.168.1.(561011) -'

or even

urlsnarf -i eth0 -n grep -Ev '192.168.1.(561011) -'

I knew a UNIX instructor who delighted in "one-liners" which is a command line where you take data in, and pipe it through as many pipes as needed to use various commands to manipulate the data to get the results desired. He was constantly pounding on his students to "know what the data looks like" and work from there. He also pointed out that there were usually several tools that could do a specific task, and that you should use the one you are most comfortable with, because the task is to get the data or answers you are looking for, not being pretty. Thus,

compton ~$ ls `echo $PATH tr ':' ' '` grep -Evc '(:^$)' 1327 compton ~$ echo $HISTSIZE 1000 compton ~$ history sed 's-^......--' tr '' '-n' sed 's-^ *--' cut -d' ' -f1 sort -u wc -l 76 compton ~$

There are 1327 "commands" in my PATH. Of the last $HISTSIZE commands, I have used just 76 - over, and over, and over...

Old guy