Here's another Text::CSV or Text::CSV_XS version:

perl -MText::CSV -lpe 'BEGIN{$c=Text::CSV->new({always_quote=>1})} $c-
+>parse($_); $c->combine($c->fields); $_=$c->string' textfile.csv
[download]

...or a little more brief...

perl -MText::CSV -lne 'BEGIN{$c=Text::CSV->new({always_quote=>1})} $c-
+>parse($_); $c->print(\*STDOUT,[$c->fields])' textfile.csv
[download]

Just substitute "Text::CSV_XS" for Text::CSV if you prefer the XS version, though it's probably not going to make much difference in one-liner world. Watch out for newlines embedded in the input CSV. ;)

An even better one liner would be to convert whichever version like to an actual script, save it in your path somewhere, and then invoke it as:

cat infile.csv | quotecsv > newfile.csv
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