Thank you for all of you who reply this question. :)

One more question on the word boundary: I read the documentation and the document said,

"is a spot between two characters that has a \w on one side of it and a \W on the other side of it (in either order), counting the imaginary characters off the beginning and end of the string as matching a \W "

Can I said the word boundary is any character in class \w?(e,g, space, tab, newline?)

In reply to Re: grep - serach limited to complete word only by Anonymous Monk
in thread grep - serach limited to complete word only by Anonymous Monk

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