I don't know a way to do so with sprintf...

Maybe the following might help you (about from perl-cookbook): 

sub Commify {
  my $text = reverse $_[0];
  $text =~ s/(\d\d\d)(?=\d)(?!\d*\.)/$1,/g;
  return scalar reverse $text;
} # Commify

[download]

Best regards,
perl -le "s==*F=e=>y~\*martinF~stronat~=>s~[^\w]~~g=>chop,print"

In reply to Re: sprintf() by strat
in thread Formatting numbers with commas by sdyates

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