如何在bash脚本输出中包含tsv / csv标头

Question

I have thousands of .tsv files where I am extracting the rows where column 2 is equal column 6.

I can use the below bash script, but I could not append column names (header) in the output.

What is the way to include header?

for x in *.tsv; do
   awk '$2==$6' <"$x" >"$x.tmp"
   mv "$x.tmp" "$x"
done

Answer 1

If you want to print based on two conditions, say so:

awk 'FNR==1 || $2==$6' file

This will print those lines that either of these:

• match the $2==$6 condition.
• are the first line.

Also, note you don't need to loop with bash, awk can do it:

awk '(FNR==1 || $2==$6) {print > FILENAME".bk"}' *.tsv