logical AND with grep

[Martin999]

Guys,

Don't laugh ...

Have a couple of variables, would like to grep for VAR1 AND var2 in a file.

AWK is a possible, but need to pass the variables into it ...

grep is possible,

grep var1 filename |grep var2 .. but not neat ...

and better ways ???

Thanks,

Martin

 

[SamBones]

This works on my Solaris box...

/usr/xpg4/bin/grep -x -E 'VAR1|var2' file.dat

The [tt]-E[/tt] allows you to specify multiple patterns, and the [tt]-x[/tt] makes it return only records that match ALL patterns (a logical AND).

Hope this helps.

 

[feherke]

Hi

Interesting [tt]grep[/tt] feature, SamBones. Could you tell me, please, more about that [tt]grep[/tt] ? I have GNU [tt]grep[/tt] 2.5.1, and -x means --line-regexp. But that logical AND feature looks much usefull.

Feherke.

http://rootshell.be/~feherke/

 

[Martin999]

ahhn, the old -x - missed that when I looked through the an page ....

Thanks you very much, i shall give it a go.

all the best

Martin

 

[Annihilannic]

I agree with Feherke, my understanding is that -x is supposed to force a match of the entire line... I don't understand why it allows partial line matches when you use alternation (i.e. |) with -E; maybe that's a bug?!

Sam, your solution doesn't do exactly what Martin requires, because it still matches a line containing only "var1" or "VAR2".

An alternative is egrep 'var1.*VAR2|VAR2.*var1' (or use grep -E if you prefer).

Annihilannic.

 

[Martin999]

Thanks Annihilannic, I think you may be right, I have a feeling (thinking back) that -x doesn't always do what you require.

You method looks good, didn't think of that ...

Martin

 

[PHV]

AWK is a possible, but need to pass the variables into it ...
Not necessarly:
v1=VAR1; v2=var2
awk "/$v1/ && /$v2/" filename

Hope This Helps, PH.
Want to get great answers to your Tek-Tips questions? Have a look at FAQ219-2884 or FAQ181-2886

 

[Martin999]

PHV,

wow, thanks, you always come up with some clever answer ...

Many thanks,

Martin