[Chester LUG] Help with a bash script

[Stuart Burns]

Dave,

Your right I do. If your going, I'm buying ;)

Stu

On 18 October 2010 22:16, David Holden <dh at iucr.org> wrote:

>
>
> On 18/10/10 21:49, Stuart Burns wrote:
> > Dave, you must be a bash Jedi!
> >
> > It does work, and I can kind of trace how it works, but would you mind
> > explaining it a bit more ?
> > Cheers muchly. I owe you a beer, if your at the LUG next week ?
>
> You still owe me a meal matey ;)
>
> IFS=' ' this set the fields seperator for the "read".
>
> basically it then loops over the rows, gets the first column (based on
> the IFS) echo's it without newline, then for each of these "col1"s cats
> the whole file again and picks out col2 (using awk) that have matching
> "col1"s, then collapses them to one line using tr '\n' ' ', the final
> echo does the newline. This all has to then be sorted and uniq'ed to
> remove repetition.
>
>  Cheers,
>
>  Dave.
>
>
>
>
> >
> > Cheers muchly. I owe you a beer, if your at the LUG next week ?
> >
> >
> > On 18 October 2010 21:26, David Holden <dh at iucr.org
> > <mailto:dh at iucr.org>> wrote:
> >
> >     Hi Stuart,
> >
> >      VERY quick hack but it may work, the grep allows # comments
> >
> >
> >     IFS=' ';
> >
> >     datfile="1.dat"
> >
> >     (
> >     cat $datfile | sort | grep -v \# | while read data
> >     do
> >      data_array=(`echo "$data"`)
> >      col1=${data_array[0]}
> >      echo -n "$col1 "
> >      cat $datfile  | sort  | grep "$col1" | awk '{print $2}' | tr '\n' '
> '
> >      echo ""
> >     done
> >     ) | sort | uniq
> >
> >
> >     Dave.
> >
> >
> >     On 18/10/10 17:44, Stuart Burns wrote:
> >     > Hi everyone,
> >     >
> >     > I am hoping someone can help me a bit here. I am creating a cript
> that
> >     > deals with volume groups. However my bash skills fall short.
> >     >
> >     > I have a file that looks like this
> >     >
> >     > Vg955-01 /dev/diska1
> >     > Vg955-01 /dev/diska2
> >     > Vg978-01 /dev/disk45
> >     > Vg978-04 /dev/disk13
> >     >
> >     > You get the picture.
> >     >
> >     > Now what I am trying to do is get all the vg parts followed by the
> >     > constituent disks. Ie above should look like:
> >     >
> >     > Vg955-01 /dev/disk1a /dev/diska2
> >     > Vg978-01 /dev/disk45
> >     > Vg978-04 /dev/disk13
> >     >
> >     > I cant really think of an easy way to do it without resorting to
> perl.
> >     > Can anyone help?
> >     >
> >     > Regards
> >     >
> >     > Stu
> >     >
> >     > _______________________________________________
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> >     > Chester at mailman.lug.org.uk <mailto:Chester at mailman.lug.org.uk>
> >     > https://mailman.lug.org.uk/mailman/listinfo/chester
> >     >
> >
> >     --
> >     Dr David Holden. (dh at iucr.org <mailto:dh at iucr.org>)
> >
> >     _______________________________________________
> >     Chester mailing list
> >     Chester at mailman.lug.org.uk <mailto:Chester at mailman.lug.org.uk>
> >     https://mailman.lug.org.uk/mailman/listinfo/chester
> >
> >
> >
> >
> > _______________________________________________
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> > Chester at mailman.lug.org.uk
> > https://mailman.lug.org.uk/mailman/listinfo/chester
>
> --
> Dr David Holden. (dh at iucr.org)
>
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> Chester mailing list
> Chester at mailman.lug.org.uk
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>
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