Re: Setting Multiple Shell Variables from One Run of awk

[Bob McGowan <bob_mcgowan@symantec.com>]

Martin McCormick wrote:
> 	Right now, I have a shell script that does the following:
>
> hostname=`echo $NEWDEV |awk 'BEGIN{FS="."}{print $1}'`
> domain=`echo $NEWDEV |awk 'BEGIN{FS="."}{print $2}'`
> top0=`echo $NEWDEV |awk 'BEGIN{FS="."}{print $3}'`
> top1=`echo $NEWDEV |awk 'BEGIN{FS="."}{print $4}'`
>
> 	That looks inefficient (dumb) so I ask, is there a way
> to assign the fields in an awk expression to shell variables as
> one runs awk once?
>
> 	Being able to do that would mean one run of awk instead
> of the 4 shown here and, if file accesses are involved, there is
> only one of those.
>
> 	Thanks.
>
> Martin McCormick WB5AGZ  Stillwater, OK 
> Systems Engineer
> OSU Information Technology Department Telecommunications Services Group

Yes, but it takes both awk and shell to do it.  And, because the awk 
script has a bunch of stuff in it that the shell recognizes, this works 
best if you can put the script in a file.  FYI, I tested this, cut and 
past to a file and the command line, it worked for me (of course, I had 
to use some bogus but properly formatted input ;).

The file would look like this:

  BEGIN{FS="."}
  {print "hostname=" $1";domain=" $2";top0=" $3";top1=" $4}

The shell part is this:

  eval $(echo $NEWDEV | awk -f awkscriptname)

I prefer the $(...) to the grave accent form, it's easier to read.  But 
if you need backwards compatibility with a shell that doesn't support 
the new syntax, use the back ticks.

--
Bob McGowan

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