Regular expression how to get value in shell script?

Question

I have to write a shell script to get value from a string .. something like that :

string="abcdef" pathName

How can I use "grep" command with the use of regular expression to get "pathName" ? Thank you

Answer 1

GNU grep has the --only-matching option:

echo 'string="abcdef" pathName' |grep --only-matching "pathName"

will output "pathName".

Update with more info on the required pattern:

echo 'string="abcdef" pathName' |grep --only-matching "[[:graph:]]*$"

Here [[:graph:]] is the character class of all non-space characters, * means zero-or-more of the preceding pattern, $ means end-of-line.
So the pattern matches the longest sequence of non-space characters at the end of the line.