UNIX for Dummies Questions & Answers

I would like to write a for loop that does the following:

I have a file called X.txt and other files called 1.txt,2.txt, .....,1000.txt.

I want to substitute the 6th column of the file X.txt with 1.txt and store the output as X.1. Then I want to do the same with X.txt and 2.txt and store the output as X.2 and so on all the way up to 1000.txt.

How do I write a for loop that achieves that? Thank you!

Like this?

Code:

#!/bin/sh

for i in *txt; do 
	[ "$i" = 'X.txt' ] || awk '{$6=f}1' f="$i" 'X.txt' > "X.${i%.txt}"
done

exit 0

It replaces the content of the sixth column on X.txt with the name `<number>.txt` and writes to X.<number>

Or this:

Code:

#!/bin/sh

for i in *txt; do 
	[ "$i" = 'X.txt' ] || awk 'NR==FNR{A[NR]=$6;next}{$6=A[FNR]}1' "$i" 'X.txt' > "X.${i%.txt}"
done

exit 0

This one replaces the sixth column of X.txt with the content of the sixth column of `<number>.txt` and writes to X.<number>