Hi all
     I am new to awk.  Trying to parse "test" from the following input
from inside a shell script.

     a=test.val.something
     echo $a | awk '{ print substr($1,1,4) }'

     The above works fine, but I would like the output  (or return
value from awk) in another shell variable.

      I tried doing the following.

      Trial 1 (did not work):
       ================
      a=test.val.something
      b=var
      echo $a | awk '{ $'$b' = substr($1,1,4) }'
      echo $var,$b

      Trial 2 (did not work):
       ================
      a=test.val.something
      b=var
      echo $a | awk '{ $'$b' = substr($1,1,4) } END { export $'$b'}'
      echo $var,$b

Thanks in advance
Sri

In article 
<1150220087.299486.229460@h76g2000cwa.googlegroups.com>,
 srihari.raghavan@gmail.com wrote:

> Hi all
>      I am new to awk.  Trying to parse "test" from the following input
> from inside a shell script.
> 
>      a=test.val.something
>      echo $a | awk '{ print substr($1,1,4) }'
> 
>      The above works fine, but I would like the output  (or return
> value from awk) in another shell variable.
> 
>       I tried doing the following.
> 
>       Trial 1 (did not work):
>        ================
>       a=test.val.something
>       b=var
>       echo $a | awk '{ $'$b' = substr($1,1,4) }'
>       echo $var,$b
> 
>       Trial 2 (did not work):
>        ================
>       a=test.val.something
>       b=var
>       echo $a | awk '{ $'$b' = substr($1,1,4) } END { export $'$b'}'
>       echo $var,$b
> 
> Thanks in advance
> Sri

    b=`echo $a | awk '{ print substr($1,1,4) }'`

Notice the grave accent (reverse quote) before and after the 
echo/awk statements.  This is how you substitute the output from 
executed commands into a shell command line.

Or if you have to return multiple values use 

    set -- `awk '/pattern/ { print $5 }' some.input.file`
    for j
    do
        echo "$j"
    done

This would find all the lines with 'pattern' in them, and print 
out the 5th field which would be set up as shell variables $1, $2, 
$3, $4, $5, .....

The for loop, loops through all the shell arguments and echos them 
out.

If you know exactly how many values you are returning, then you 
just access them via $1, $2, $3, etc....

                                        Bob Harris

On 2006-06-13, srihari.raghavan@gmail.com wrote:
> Hi all
>      I am new to awk.  Trying to parse "test" from the following input
> from inside a shell script.
>
>      a=test.val.something
>      echo $a | awk '{ print substr($1,1,4) }'
>
>      The above works fine, but I would like the output  (or return
> value from awk) in another shell variable.
>
>       I tried doing the following.
>
>       Trial 1 (did not work):
>        ================
>       a=test.val.something
>       b=var
>       echo $a | awk '{ $'$b' = substr($1,1,4) }'
>       echo $var,$b
>
>       Trial 2 (did not work):
>        ================
>       a=test.val.something
>       b=var
>       echo $a | awk '{ $'$b' = substr($1,1,4) } END { export $'$b'}'
>       echo $var,$b

    I wouldn't use awk; the shell can do it:

var=${a%%.*}

    Or, in a Bourne shell"

IFS=.
set -f
set $a
var=$1

    With awk, you would use command substitution:

var=$( echo "$a" | awk -F. '{print $1}' )


-- 
   Chris F.A. Johnson, author              <http://cfaj.freeshell.org>
   Shell Scripting Recipes: A Problem-Solution Approach (2005, Apress)
   ===== My code in this post, if any, assumes the POSIX locale
   ===== and is released under the GNU General Public Licence

srihari.raghavan@gmail.com wrote:
> Hi all
>      I am new to awk.  Trying to parse "test" from the following input
> from inside a shell script.
> 
>      a=test.val.something
>      echo $a | awk '{ print substr($1,1,4) }'

Have you tried this:

$ b=`echo $a | awk '{ print substr($1,1,4) }'`

You should find a good bash reference and find out what the back-quote 
"`" does.  The 'Bash-programming-intro' Linux Howto I do not recommend.

http://www.tldp.org/HOWTO/Bash-Prog-Intro-HOWTO.html

'The Unix Programming Environment' by Kerninghan and Pike is a good 
book.  It is old though.

srihari.raghavan@gmail.com wrote:
> Hi all
>      I am new to awk.  Trying to parse "test" from the following input
> from inside a shell script.
> 
>      a=test.val.something
>      echo $a | awk '{ print substr($1,1,4) }'

Have you tried this:

$ b=`echo $a | awk '{ print substr($1,1,4) }'`

You should find a good bash reference and find out what the back-quote 
"`" does.  The 'Bash-programming-intro' Linux Howto I do not recommend.

http://www.tldp.org/HOWTO/Bash-Prog-Intro-HOWTO.html

'The Unix Programming Environment' by Kernighan and Pike is a good book. 
  It is old though.

Hi all
    Thank you all for your time.  Works fine now.

Sri