I am having difficulty understanding what you have written. It would be easier if you included sample input and output, wrapped in code tags, as described in How do I post a question effectively?.

Is there a reason you are committed to using a one-liner instead of a more traditional multi-line script? That could give you a great deal of control in how you cycle over your files (opendir, readdir) and how they are formatted. As well, since you are dealing with CSV, it might make sense to use Text::CSV in case there is escaping. My general rule is I only use a one-liner when I'm doing a quick task once - by posting a question, it feels like you no longer meet the quick criterion.

If you need to know what file name you are dealing with in a -n context, it's stored in $ARGV. So maybe you want something closer to 


perl -F"\t" -lane '$, = ","; print $ARGV, $F[21], $F[3]' *.gcount > Af
+1gcount.csv

[download]

Update: Fixed broken link. Thanks NaN.

#11929 First ask yourself `How would I do this without a computer?' Then have the computer do it the same way.

In reply to Re: Printing columns to a single file by kennethk
in thread Printing columns to a single file by anisha3

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