I have an 8-column input tab-delimited .txt file and wish to print the contents of column 3 + 8 when the value held within column 8 is >0.

I've tried:

perl -lane 'print "$F[2]\t$F[7]" if $F[7] > 0' < input.txt

However this only returns a single line (the first line) when there are multiple matching lines. I want it to iterate over every line instead. What have I done wrong?

For example, if my input file contains:

77    *    10    0    *    *    0    340

141    *    40    0    *    *    0    240

The output file will only contain:

10    340

In reply to One-liner only checking the first line of the input file by TJCooper

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