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Grep for a string at a certain position

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# 1  
Old 09-12-2013
Grep for a string at a certain position
trying to grep for a string at a certain position in a commands output in order to use it as a variable:

Code:
route
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
default         192.168.2.1     0.0.0.0         UG    0      0        0 wlan1
192.168.2.0     *               255.255.255.0   U     0      0        0 wlan1

I want grep to pull out from the 'route' function, the network interface being used, always in that position, I just don't know how to specify the position, ideally to work regardless of the name, be it wlan0/1 or eth0 etc.

Many thanks.
# 2  
Old 09-12-2013
try sth like this

Code:
grep -E "wlan[01]$|eth0$" file1

default         192.168.2.1     0.0.0.0         UG    0      0        0 wlan1
192.168.2.0     *               255.255.255.0   U     0      0        0 wlan1

# 3  
Old 09-12-2013
What is 'file1' referring to there mate?
# 4  
Old 09-12-2013
file1 is referring file here you can also use pipe to direct your input to awk.

Code:
route | grep -E "wlan[01]$|eth0$"

# 5  
Old 09-12-2013
Try
Code:
route | grep -o "[^ ]*[0-9]$"
eth0
eth0

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