topic Re: grep - how to exclude fields ? in Operating System - Linux

grep - how to exclude fields ?

Piotr Kirklewski — Mon, 26 Mar 2007 11:34:11 GMT

Hi there

bdf |grep /stand

output:

/dev/vg00/lvol1 295024 59344 206176 22% /stand

I nead o exclude all but lvol1 and /stand

Can anyone help ?

Cheers

Re: grep - how to exclude fields ?

john korterman — Mon, 26 Mar 2007 11:38:09 GMT

Hi,

try something like this:

$ bdf | grep stand| awk '{print $1,$NF}'

regards,
John K.

Re: grep - how to exclude fields ?

Oviwan — Mon, 26 Mar 2007 11:40:09 GMT

Hey

bdf | grep /stand | awk ' { print $1" "$NF}'

Regards

Re: grep - how to exclude fields ?

James R. Ferguson — Mon, 26 Mar 2007 11:43:57 GMT

HI:

The simple way:

# bdf|grep -v -e /stand -e lvol1

Regards!

...JRF...

Re: grep - how to exclude fields ?

Hein van den Heuvel — Mon, 26 Mar 2007 12:46:12 GMT

With grep you get whole lines.
No ifs or buts.
So grep needs help, typically awk or cut.
John K, shows a fine example of this helping.

However, why not let awk (or perl) do it all?

$ bdf | awk '/stand/ {print $1,$NF}'

Also, somehow I'm thinking this is not your end goal. What problem are you really trying to solve ?!

Regards,
Hein.

Re: grep - how to exclude fields ?

A. Clay Stephenson — Mon, 26 Mar 2007 12:55:14 GMT

... and to fix one other problem that you haven't yet anticipated, I suggest that you use bdfmegs rather than bdf. Bdfmegs is a Bill Hassell script that almost always outputs like bdf. The "almost always" is the significant part. Search the Forums for bdfmegs and you should have no trouble finding it.

Re: grep - how to exclude fields ?

TwoProc — Mon, 26 Mar 2007 13:05:08 GMT

to get JUST the output:

lvol1 stand

run:

bdf | grep /stand | sed -e "s/\// /g" -e "s/ */ /g" | cut -d " " -f 4,9

Note: the first sed expression has a single space before the "/g", and the second one has *two spaces* after the "s/" and a single space before the "/g".

I'm guessing that since you know that /stand is in vg00 you're not interested in the whole /dev/vg00/lvol1 part of the string.

Re: grep - how to exclude fields ?

TwoProc — Mon, 26 Mar 2007 13:39:36 GMT

Lots of ways to get that done, mainly because there are a number of sources for that information: commands "df" and "bdf", as well as files "/etc/fstab" and "/etc/mnttab" .

An easier one than the previous posting would be:

> df | grep stand | cut -b -15,33-42

And actually
> df -n | grep stand

gets you pretty close to what you asked for w/o stream edits.

If you're wanting make sure to avoid the "bdf" line wrap problem indirectly mentioned in a previous posting use the contents /etc/mnttab instead:

> grep stand /etc/mnttab | cut -d "/" -f 4,5 | cut -d " " -f 1,2

gives:

lvol1 /stand