topic Re: exact match in Operating System - HP-UX

exact match

Norman_21 — Mon, 08 Dec 2008 05:53:11 GMT

Hi guys,

I'm so tired to even think so can you please advice how can I get the exact string without getting the other similar one?
Get 10 easy points!

# mount|awk '/vghp17uv/'
/uvtmp on /dev/vghp17uvtmp/lvol1 ioerror=mwdisable,largefiles,delaylog,dev=40040001 on Sun Nov 16 01:08:38 2008
/u1 on /dev/vghp17uv/lvol1 ioerror=mwdisable,largefiles,delaylog,dev=40020001 on Sun Nov 16 01:08:39 2008

Here is the problem. It's not getting the right one?
# mount|awk '/vghp17uv/ {print $1}'|cut -d / -f 2
uvtmp
u1

Re: exact match

Dennis Handly — Mon, 08 Dec 2008 07:11:36 GMT

You need to include the "/" in the pattern:
mount | awk '/\/vghp17uv\// {print substr($1,2)}'

If you are using awk, don't need cut.

Re: exact match

Venkatesh BL — Mon, 08 Dec 2008 07:52:12 GMT

Bang on! Just to note - even though it looks like 'V' (capital 'v'), it is actually, '\' followed by '/'

Re: exact match

Hein van den Heuvel — Mon, 08 Dec 2008 13:13:34 GMT

in PERL the Regular expressions have this nice \b to match on a word boundary.

The solution then becomes...

mount | perl -ne 'print $1 if /^.(\w+)\s.*\bvghp17uv\b/'

fwiw,
Hein.

Re: exact match

James R. Ferguson — Mon, 08 Dec 2008 13:22:59 GMT

Hi:

You could also use Perl which allows a variety of delimiters for regular expressions and makes using the '/' character simple to visualize.

# mount|perl -nale 'print $F[0] if $F[2]=~m{/vghp17uv/}'
/u1

This also avoids having to worry about the length of fields. Notice that Perl numbers the first field as zero whereas 'awk' counts from one.

Regards!

...JRF...

Re: exact match

Fredrik.eriksson — Tue, 09 Dec 2008 15:57:52 GMT

If you're searching with regexps you need to delimit your search... vghp17uv is in both vghp17uv and vghp17uvtmp.

mount | egrep "/vghp17uv/" | cut -d'/' -f2

this should work better (since egrep doesn't bother with that // to specify a search) and give you a more exact match.

Best regards
Fredrik Eriksson

Re: exact match

Dennis Handly — Tue, 09 Dec 2008 22:23:21 GMT

>Fredrik: since egrep doesn't bother

There is no reason to use the egrep hammer, fgrep/grep is fine. You can also use grep -w and leave out the "/".

Re: exact match

Fredrik.eriksson — Wed, 10 Dec 2008 08:17:01 GMT

True, seems like I was abit tired to when i wrote it :P
grep would do it fine since no regexp is involved :P

Re: exact match

Norman_21 — Tue, 27 Jan 2009 18:09:08 GMT

Closed