Linux script that writes and displays an ip address.

[GamerGry123]

I was doing a script in Linux that saves and displays the ip address in cmd

 

nano address

 

Then at the very beginning of the file I wrote #!/bin/bash

So that Linux knows this is a script.

 

Further in the file I wrote: 

ifconfig > plik.txt
grep "inet" > plik.txt
cat plik.txt

 

Then I gave the script permissions:
chmod + x adres

 

I ran the script:
./address

 

 

I'm still sending photos. I did the script creation right this is how each script is created.
I also ran the script well and so each script runs.

Maybe some command is wrongly written in the script.

 

[Dutch_Master]

It doesn't work. I'll leave it for you to figure out why. So you can learn

 

Spoiler

hints: spelling & permissions

 

[GamerGry123]

18 minutes ago, Dutch_Master said:

It doesn't work. I'll leave it for you to figure out why. So you can learn

 

  Reveal hidden contents

hints: spelling & permissions

 

I know it doesn't work. I was looking on the internet why it doesn't work but I don't know. When I enter the same letters in the terminal, it works normally, but I don't know why the same commands in the script don't work.

[C2dan88]

Its not working because you are searching for "inet" with no input

[flindeberg]

3 hours ago, GamerGry123 said:

ifconfig > plik.txt
grep "inet" > plik.txt
cat plik.txt

1. Can you explain what you think each line does? And in particular what you think ">" does?
2. Is that really the best way of solving this? Aren't you interesting in taking the output of ifconfig and directly filtering for what you are looking for?

[Nayr438]

#!/bin/bash

#Set the Device to be used.
DEVICE="enp4s0"

#Set the File you want to save to.
OUTPUT="./local_ip.txt"

#Obtain IP Address
IP=`ifconfig $DEVICE | egrep -o 'inet [0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}' | cut -d' ' -f2`

#Ouput to File
echo $IP > $OUTPUT

[igoshin]

I would do like this:

 

#!/bin/bash

outputfile=/tmp/myip

ip -4 a l  $(ip route |head -1 | awk '/default/ { print $5 }') |  awk '/inet/ { print $2 }' | awk -F'/' {'print $1'} | tee ${outputfile}