The first thing you want to check is the grep documentation. This together with a few practice with hashes will easily solve your problem.

Many people here get upset with these questions that read like "Hey, I have a problem. Gimme a solution for free. Oh, I don't mind if you improve on what I didn't tell you." Take a look at how Problem in date checking script was received by comments Re: Problem in date checking script and Re: Problem in date checking script. The reference How (Not) To Ask A Question will be a good reading for you as well. It will bring you more sympathetic and useful answers, while helping you to revert your negative XP score.

A one-liner such as this may count the number of lines the word "hello" was found, just like $ grep hello text.out | wc -l (mentioned by derby at Re: grep command). 

$ perl -n -e '$count++ if /\bhello\b/; END { print $count }' text.out

[download]

A very simple modification will give you what you want. It has to do with the global modifier in regexes (see perlretut).

Note: I've changed the simple /hello/ to /\bhello\b/ because sanku said he was looking for words.

In reply to Re: grep command by ferreira
in thread grep command by sanku

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