I have several perl functions that are running on a web server that print the web browser. Is there a way to determine whether a web browser has already been sent the web headers? A very simple example of code that I am using follows.

The problem is that when the headers get printed twice, this appears: "Content-Type: text/html; charset=ISO-8859-1". Ideally this check would take place in the "send_headers" function. The way I am doing it now is a sloppy, sloppy hack. 
sub my_func {

  my($check) = @_;

  if ($check eq "no") {
    &send_headers;
  }

  #do stuff here

  return();

}

sub send_headers {
 my $query = CGI:new();
 print $query->header;
}

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In reply to Web Headers by Anonymous Monk

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