Here is a pointer: Instead of printing the data, store it in a data structure that is declared outside the outer foreach loop. Then when you are done with all input files, write the output into a single file.

If you haven't yet worked with nested data structures in Perl, I can recommend perlreftut, perldsc and perllol (the latter for arrays of arays).

Perl 6 - the future is here, just unevenly distributed

In reply to Re: Appending new column data to CSV file? by moritz
in thread Appending new column data to CSV file? by rnaeye

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