My impression is that Discipulus's
    perl -lanF',' -e "print join',',map {$_ ? $_ : 'NULL'} @F " testcsvnull.txt
is running under Windoze, and your
    <$ perl -lanF',' -e "print join',',map {$_ ? $_ : 'NULL'} @F " 1.txt
is running under *nix. Fix the quoting as appropriate to your OS shell and give it another try.

Give a man a fish:  <%-{-{-{-<

In reply to Re^3: insert null in missing places of csv by AnomalousMonk
in thread insert null in missing places of csv by ukhare

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