Set an external variable in awk

I have written a script in which I want to count the number of columns in data.txt . My problem is I am unable to set the x in awk script. Any help would be highly appreciated.

while read p; do
  x=1;
  echo $p | awk -F' ' '{x=NF}'
  echo $x;
  file="$x"".txt";
  echo $file;
  done <$1

data.txt file:

4495125 94307025    [e-mail]   94307025.094307025  12443
stazla  [e-mail]  1992/.:1
1447585 [e-mail] h1st@1
saknit  [e-mail]   1233    1990

Expected output:

5.txt
3.txt
3.txt
4.txt

My output:

1.txt
1.txt
1.txt
1.txt

Answer

You just cannot import variable set in Awk to a shell context. In your example the value set inside x containing NF will be not reflected outside.

Either you need to use command substitution($(..)) syntax to get the value of NF and use it later

x=$(echo "$p" | awk '{print NF}')

Now x will contain the column count in each of the line. Note that you don’t need to use -F' ' which is the default de-limiter in awk.

Besides your requirement can be fully done in Awk itself.

awk 'NF{print NF".txt"}' file

Here the NF{..} is to ensure that the actions inside {..} are applied only to non-empty rows. The for each row we print the length and append the extension .txt along with it.