topic Re: Newbie grep question... in Operating System - HP-UX

Newbie grep question...

Gene Laoyan — Mon, 06 Nov 2006 12:00:17 GMT

Here's my commandline...
ioscan -fnC disk | grep '/dev/rdsk/c7t0d1'

It returns the following...
/dev/dsk/c7t0d1 /dev/dsk/c7t0d1s2 /dev/rdsk/c7t0d1 /dev/rdsk/c7t0d1s2
/dev/dsk/c7t0d1s1 /dev/dsk/c7t0d1s3 /dev/rdsk/c7t0d1s1 /dev/rdsk/c7t0d1s3

I only want the first line, how do I do that?

If I want only the second line, how do I do that?

Thanks

Re: Newbie grep question...

Geoff Wild — Mon, 06 Nov 2006 12:04:00 GMT

ioscan -fnC disk | grep '/dev/rdsk/c7t0d1' |head -1

Rgds...Geoff

Re: Newbie grep question...

Victor BERRIDGE — Mon, 06 Nov 2006 12:06:15 GMT

And for the last line:
ioscan -fnC disk | grep '/dev/rdsk/c7t0d1' |tail -1

All the best
Victor

Re: Newbie grep question...

Ivan Krastev — Mon, 06 Nov 2006 12:07:41 GMT

If you want only 1st line use head:

ioscan -fnC disk | grep '/dev/rdsk/c7t0d1' | head -n1

regards,
ivan

Re: Newbie grep question...

Pete Randall — Mon, 06 Nov 2006 12:07:48 GMT

Or, for the second line,

ioscan -fnC disk | grep '/dev/rdsk/c7t0d1' |head -2 |tail -1

Pete

Re: Newbie grep question...

Jonathan Fife — Mon, 06 Nov 2006 12:08:55 GMT

If you only want grep to return a line with the exact pattern you specified and no leading or trailing non-white characters you can use the -w argument.

ioscan -fnC disk | grep -w '/dev/rdsk/c7t0d1'

Your second question is a bit trickier. What would be your criteria for returning only the second line? The fact that it is second? The fact that it doesn't include the /dev/rdsk/c7t0d1 string except with additional characters at the end? The fact that it includes s1 and s3 and not s2?

Re: Newbie grep question...

Gene Laoyan — Mon, 06 Nov 2006 12:29:41 GMT

Points awarded!
Thanks everyone!!!