Using grep how to get whole word with numeric digits only the word in line

Question

I facing an issue when I use this command

"grep  RTB4"

The output is:

192.168.1.1   RTB4-NODE-1

I only have to get RTB4-NODE-1 in output.

How can I do this?

Answer 1

Assuming by "word" you mean anything not interrupted by spaces:

grep RTB4 | tr ' ' '\n' | grep RTB4

You can add more characters to the tr command if you need to split on other forms of whitespace.

Answer 2

I suspect what you really want is:

awk '$NF~/RTB4/{print $NF}' file

so it only looks for the regexp in and prints the last space-separated field on each line.

Answer 3

This gnu awk (gnu due to multiple characters in RS) should do:

awk -v RS=" *" '/RTB4/'

eks:

echo "192.168.1.1   RTB4-NODE-1" | awk -v RS=" *" '/RTB4/'
RTB4-NODE-1