How to pass an awk variable to shell scripts?

[pengpeng]

Hi,

I need do some calculate in awk script, then pass the values out. For example,

#!/bin/bash
cat example.txt | awk -v T_C=$TC T_V=$TV '{
if( $0 ! /^ABC/ ){
T_C=T_C+1;
}
if( $0 ! /^XYZ/ ){
T_V=T_V+1;
}
}'
echo $TC
echo $TV

How could I pass the values of T_C and T_V out to my shell script?

Thanks.

 

[vgersh99]

eval `nawk -f var.awk < /dev/null`
echo ${aPOW2}

#-------------- var.awk
BEGIN {
a=2
b=4
printf(&quot;aPOW2=%d ;bPOW2=%d\n&quot;, a*a, b*b);
}


vlad
+----------------------------+
| #include<disclaimer.h> |
+----------------------------+

 

[marsd]

Typically you could use a shell function for this.
Something like..

function ret_from_awk() {
pat=$1
val=$2
fname=$3

awk -v p=$pat -v vl=$val ' {
if ($0 !~ p) {
vl++
}
} END {printf(&quot;%d\n&quot;,vl)
}' $fname
return
}
ex:
ret_from_awk t..* 1 scrap.txt
3

 

[marsd]

Vlad's is better.
You would also need to store the functions output in
the variable you are using for my example.

a1=`ret_from_awk t..* 1 scrap.txt`

 

[pengpeng]

It works after I used your method.

Thank you both very much.

Pengpeng

 

[suchupramod]

Hi ,
I have the same problem, and I think I did not understand from the code snippet how to get back variables from awk to shell.
My code looks like this:
read string
awk -v VAR=&quot;$string&quot; 'BEGIN {
split (VAR,arr,&quot; &quot
{print arr[2]}
}'

I want to get the values stored in array arr to the shell.
Can someone help.

~

 

[vgersh99]

myVar=`echo &quot;${string}&quot; | nawk '{print $2}'`

vlad
+----------------------------+
| #include<disclaimer.h> |
+----------------------------+