[SOLVED] Can't get sed to work

battles · 11-18-2014, 10:43 AM

I am getting my current IP address like this:

myIP=$(ip addr show dev eth0 | grep "inet " | cut -d" " -f6 | grep -o '[0-9]\{1,3\}\.[0-9]\{1,3\}\.[0-9]\{1,3\}\.[0-9]\{1,3\}')

(myIP then = 12.34.567.890)

When I try this, it can't find it to delete it out of the file:
(line in file = '1 12.34.567.890')

sed -i "/$myIP/d" temp.txt # remove my IP for safety

When I do this, it finds it and deletes it:

myIP="12.34.567.890"
sed -i "/$myIP/d" temp.txt # remove my IP for safety

Any suggestions? Thanks.

smallpond · 11-18-2014, 12:05 PM

I would read the IP using system functions instead of parsing command output:

Code:

myIP=$(perl -MSocket -MSys::Hostname -e '@f=gethostbyname hostname(); print inet_ntoa($f[4])')
echo $myIP
192.168.77.232

battles · 11-18-2014, 12:11 PM

Nice example, I didn't even know that perl could be executed that way. Unfortunately, the sed still didn't delete the ip address in temp.txt.

battles · 11-18-2014, 12:29 PM

Quote:

Originally Posted by smallpond

I would read the IP using system functions instead of parsing command output:

Code:

myIP=$(perl -MSocket -MSys::Hostname -e '@f=gethostbyname hostname(); print inet_ntoa($f[4])')
echo $myIP
192.168.77.232

Incidentally, this gives my address as: 127.0.0.1. Mine gives the correct IP.

battles · 11-18-2014, 12:38 PM

This actually was working. Just an oversight concerning the wrong IP address.