It looks like $file = '"'.$file; would be really slow because you are copying the entire file.

Anyway, it looks like you only need one regular expression (and transliteration): 

my $file = <$INPUT>;
$file =~ s/(?:(?<=^)|(?<=\t))([^\t\n]*)(?=[\t\n])/"$1"/mg;
$file =~ tr/\t/,/;

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In reply to Re: Making CSV Files from Tab Delimited Files by jwkrahn
in thread Making CSV Files from Tab Delimited Files by MajingaZ

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