topic Re: AWK in Operating System - HP-UX

AWK

Sundar_7 — Tue, 19 Feb 2002 09:43:39 GMT

Hi all,

I have one query in AWK..

I am trying to assign some value to a variable and then trying to access that variable out of awk..

But then I could not succeed in doing that..

Say for ex

$ echo "one two" | awk '{var=$1}'

$ echo "$var"

I would like to use the value of variable "VAR" out of awk.

Is there any way to do it ?

I checked the awk documentation as well..

But then could not find what I want..

So..Can any one pls give me some input on this issue ?

Thanks

Sundar

Re: AWK

Corthouts Carlo — Tue, 19 Feb 2002 09:49:58 GMT

Hi,

Maybe try :

export var=`echo "one two" | awk '{print $1}'

echo $var then shows 'one'

Re: AWK

Peter Kloetgen — Tue, 19 Feb 2002 09:50:11 GMT

Hi,

first you have to give variables to AWK when using the -v option

awk -v var=value

you can now use the variable in awk- programs.

And you have the possibility to put the output of awk into a variable using command substitution:

var=`cat file |awk '{print $5}'`

after this "trick", you can use var in your scripts.

Allways stay on the bright side of life!

Peter

Re: AWK

Peter Kloetgen — Tue, 19 Feb 2002 09:54:27 GMT

Hi,

there is a little typo in Corthouts Carlos script, he forgot to close the backticks for the command substitution.

Additional:

when using a ksh or a POSIX shell you can also use the following syntax:

var=$(command1 | command2 | command3)

this is bad if you use a Bourne shell, which doesn't know this.

Allways stay on the bright side of life!

Peter

Re: AWK

Robin Wakefield — Tue, 19 Feb 2002 10:11:55 GMT

Hi Sundar,

# a=fred
# echo hello | awk '{print $0,var}' var=$a
hello fred

should do it for you.

Rgds, Robin.

Re: AWK

Sundar_7 — Tue, 19 Feb 2002 14:53:29 GMT

Friends & Gurus,

I know there are two possible ways to take out the value from AWK to a variable

$ var="Value"

$ awk -v a=$var '{print a}' /tmp/somefile

But then that is not what I am trying to do..

We can only pass down the values from Shell to AWK ..

I am looking out for a way to pass down the value from AWK to SHELL..i.e I will assign some value to a variable inside AWK and then I would like to refer that Variable out of AWK in the SHELL...

and when it comes to assigning variable a value like this

$ var=$(awk '{inst}' files)

I beleive We can assign value to only one variable..

But I am looking to assign value to MORE THAN one VARIABLE..and then refer that variable out of AWK..

Hope and wish I am clear and pls let me have some inputs on these things

Thanks

Sundar
Sundarhp@hotmail.com

Re: AWK

A. Clay Stephenson — Tue, 19 Feb 2002 15:03:05 GMT

In that case what you need to do is someting like this:

awk { ..... } | read var1 var2 var2

You can get the idea by doing something like this:

echo "XX" "YY" "ZZ" | read var1 var2 var3

$var1 -> XX
$var2 -> YY
$var3 -> ZZ

Re: AWK

Peter Kloetgen — Tue, 19 Feb 2002 15:11:47 GMT

Hi,

of course you can read several variables the way described by Clay. Or you can redirect the output of the awk- command into a file:

awk '{action}' file > "file_name"

and work with the file after that....

Allways stay on the bright side of life!

Peter