Linux bash: when to use egrep instead of grep?

Posted by Michael Mao on Stack Overflow See other posts from Stack Overflow or by Michael Mao
Published on 2010-04-07T01:53:05Z Indexed on 2010/04/07 2:13 UTC
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homework

Hi all :

I am preparing for a Linux terminal assessment now, I tried to Google and found most resources are referring to the basic "grep" rather than the more powerful "egrep" -- well, that is at least what the professor said in lecture.

I am always working with small samples so performance tuning is a thing too far away.

So basically I'd like to know are there any areas where I must switch to egrep to do it in a better way? Is it safe to work with basic "grep" as for now? will there be potential risks?

Sorry about my limited knowledge on Linux shell commands, the man page looks like a maze to me and honestly I haven't put much time in understanding all the features both command provide.

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