UNIX for Dummies Questions & Answers

perldoc -q count
Found in /usr/share/perl/5.8/pod/perlfaq4.pod
  How can I count the number of occurrences of a substring within a string?
    There are a number of ways, with varying efficiency. If you want a count
    of a certain single character (X) within a string, you can use the
    "tr///" function like so:

        $string = "ThisXlineXhasXsomeXx'sXinXit";
        $count = ($string =~ tr/X//);
        print "There are $count X characters in the string";

    This is fine if you are just looking for a single character.
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awk '$0=$0OFS NF-1' FS=, file