In Linux, you can parse an IP address using various command-line tools like awk, sed, or cut. Here are a few examples:
Using awk
You can use awk to parse an IP address from a file or output by specifying the field separator as a dot (.). For example, if you have a file called ip.txt containing an IP address on each line, you can extract the first three octets of the IP address using the following command:
awk -F '.' '{print $1"."$2"."$3}' ip.txt
This will output the first three octets of the IP address, separated by dots.
Using sed
You can also use sed to extract a specific part of an IP address. For example, if you have an IP address 192.168.1.100 and you want to extract the third octet, you can use the following command:
echo "192.168.1.100" | sed 's/\([0-9]\+\)\.\([0-9]\+\)\.\([0-9]\+\)\.\([0-9]\+\)/\3/'
This will output the third octet of the IP address, which is 1 in this case.
Using cut
You can use cut to extract a specific field from a string. For example, if you have an IP address 192.168.1.100 and you want to extract the third octet, you can use the following command:
echo "192.168.1.100" | cut -d '.' -f 3
This will output the third octet of the IP address, which is 1 in this case.
These are just a few examples of how you can parse an IP address in Linux using command-line tools. The specific tool and command you use may depend on your specific use case and requirements.