[olug] Unix Tip: GET YOUR IP-ADDRESS (long explanation)

CM Miller cmmiller1973 at yahoo.com
Thu Mar 20 20:23:01 UTC 2003


I know what all of these commands mean, but why do
something like this at the command line?  A script,
yes. 

-Chris 

--- Eric Penne <epenne at olug.org> wrote:
> ifconfig | grep "inet addr" |  grep -v "127.0.0.1" |
> awk '{print $2;}' |
> awk -F':' '{print $2;}'
> 
> 
> Here is a rundown on this command for the newbies.
> 
> 1) ifconfig is usually located in /sbin/ifconfig
> shows the network
> interfaces that are up and how they are configured.
> 
> 2) grep pulls lines out of the ifconfig info that
> contain inet addr
> 
> 3) grep -v inverts.  It prints all the lines that
> don't have 127.0.0.1
> in them.
> 
> 4) awk looks at the info and pulls the second field
> out, where the
> fields are separated by whitespace by default.
> 
> 5) Then awk -F':' is used again to pull the second
> field out, where the
> fields are separated by a colon.
> 
> The individual outputs follow:
> 
> 1)
> 
> eth0      Link encap:Ethernet  HWaddr
> 00:80:AD:0C:BA:43
>           inet addr:192.168.1.42 
> Bcast:192.168.255.255
> Mask:255.255.0.0 UP BROADCAST RUNNING MULTICAST 
> MTU:1500
> Metric:1
>           RX packets:34866 errors:0 dropped:0
> overruns:0 frame:0
>           TX packets:5882 errors:0 dropped:0
> overruns:0 carrier:0
>           collisions:0 txqueuelen:100
>           RX bytes:7133322 (6.8 MiB)  TX
> bytes:850473 (830.5 KiB)
>           Interrupt:3 Base address:0xd800
> 
> lo        Link encap:Local Loopback
>           inet addr:127.0.0.1  Mask:255.0.0.0
>           UP LOOPBACK RUNNING  MTU:16436  Metric:1
>           RX packets:8 errors:0 dropped:0 overruns:0
> frame:0
>           TX packets:8 errors:0 dropped:0 overruns:0
> carrier:0
>           collisions:0 txqueuelen:0
>           RX bytes:400 (400.0 b)  TX bytes:400
> (400.0 b)
> 
> 2)
>           inet addr:192.168.1.42 
> Bcast:192.168.255.255
> Mask:255.255.0.0 inet addr:127.0.0.1  Mask:255.0.0.0
> 
> 3)
>           inet addr:192.168.1.42 
> Bcast:192.168.255.255
> Mask:255.255.0.0
> 
> 4)
> addr:192.168.1.42
> 
> 5)
> 192.168.1.42
> 
> 
> Now don't we all love the pipe command.  Hopefully
> if you are having
> trouble with the above command this explanation can
> step you through the
> issues.
> 
> Eric
> 
> 
> 
> _______________________________________________
> OLUG mailing list
> OLUG at olug.org
> http://lists.olug.org/mailman/listinfo/olug


=====
Winning an argument on the internet is like getting 1st place at the Special Olympics

*****************************************
GAIM ID:  cmmiller1973
*****************************************

__________________________________________________
Do you Yahoo!?
Yahoo! Platinum - Watch CBS' NCAA March Madness, live on your desktop!
http://platinum.yahoo.com


More information about the OLUG mailing list