I should have thought of quoting them ... thanks for all of the responses
----- Original Message -----
From: "Robert Locke" <lists@xxxxxxxxx>
To: "For users of Fedora Core releases" <fedora-list@xxxxxxxxxx>
Sent: Thursday, February 02, 2006 9:53 AM
Subject: Re: advanced grep question
On Thu, 2006-02-02 at 09:39 -0600, Steven J Lamb wrote:
what I am looking for is information on how to use grep in the following
way. I want to do essentially this
grep (string1|string2|string3) filename
I would use this to search filename for either string1, string2 or string
3
instances
I realize I could do the following but would like to use it as one grep
statement as I believe it should be more efficient.
>tmp;
grep string1 filename >>tmp;
grep string2 filename >>tmp;
grep string3 filename >>tmp
as this would be defined in a normal regular expression. grep claims to
be
able to use this functionality as best I can tell ... it is documented in
the man page and it says
Two regular expressions may be joined by the infix operator |; the
resulting regular expression matches
any string matching either subexpression.
I have not been able to find an example of this anywhere and have tried
several forms of the syntax but no luck. my command interpreter keeps
trying
to use the pipe instead of letting grep have it.
any one have any thoughts
thanks
With basic regular expression you need to quote the "|" so it would be
something like this:
grep 'string1\|string2\|string3' file
The alternative would be to get in to extended regular expression with
egrep or grep -E which would look like:
egrep 'string1|string2|string3' file
HTH,
--Rob
--
fedora-list mailing list
fedora-list@xxxxxxxxxx
To unsubscribe: https://www.redhat.com/mailman/listinfo/fedora-list
