You want to read perlopentut. That should answer your questions. Specifically, I think you don't want system but instead want to open the external command with a leading pipe.

  open(PRINTER, "| lpr -Plp1")    || die "can't run lpr: $!";
  print PRINTER "stuff\n";
  close(PRINTER)                  || die "can't close lpr: $!";

[download]

However, you'll also want to read perlsec.

Cheers,
Ovid

New address of my CGI Course.

In reply to Re: Constructing STDIN for an external progam by Ovid
in thread Constructing STDIN for an external progam by Anonymous Monk

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