How to replace the output (new html page)?

Gary Yang has asked for the wisdom of the Perl Monks concerning the following question:

Hi,
I do not know if this is a Perl or html question. Please help.
My Perl script runs at Server Site. When the script gets called, it outputs (prints) a progress html page displayed at Client site. When the program ends, it generates a new html page. This new html page should replace that progress page. However, instead of replacing the ProgressPage, the new html page is appended to ProgressPage. I use Perl here doc to print html pages. Below is the sample code.

First, print Progress Page.

Print <<ProgressPage;
<html>
   <head>
Е..
    </head>
   <body>
Е..
  </body>
</html>
ProgressPage
[download]

Then, print the new HTML page. I want the new HTML page (NewPage) replaces ProgressPage. But, instead of replacing it, NewPage appends to ProgressPage. Can someone tell me how to replace ProgressPage with NewPage?

print <<NewPage;
<html>
   <head>
   ЕЕ
   </head>
   <body>
    ЕЕ
   </body>
</html>
NewPage
[download]

Comment on How to replace the output (new html page)? Select or Download Code

Replies are listed 'Best First'.
Re: How to replace the output (new html page)? by Anonymous Monk on Jan 19, 2012 at 04:04 UTC
Its an issue of http. See Watching long processes through CGI (Aug 02) and Proc::Background	[reply]
Re: How to replace the output (new html page)? by Anonymous Monk on Jan 19, 2012 at 11:24 UTC
You are searching for some kind of server push with HTTP. It can be done -- look at a Bugzilla's after-search "munching bugs" screen. I'm not familiar with it, but I suspect it is a case of sending two files with "Content-Disposition: inline" and some sort of MIME splitting to distinguish the two HTML pages. Try to find out more by reading the Bugzilla source.	[reply]
Re^2: How to replace the output (new html page)? by Anonymous Monk on Jan 19, 2012 at 17:32 UTC
As the other Anon hinted at, server push technology (originally introduced by Netscape -- yes, it's that old) appears not to work in MSIE, but the other major browsers seem to handle it fine. An alternative solution would be to save your second HTML page (temporarily?) to a publicly-accessible place, and redirect/link there once you are done. Some strategically placed output flushing might work best there (but might also be broken by a change of your web server or CGI serving configuration).	[reply]
Re^2: How to replace the output (new html page)? by Anonymous Monk on Jan 19, 2012 at 11:43 UTC
server push ddg://server push site:stonehenge.com ddg://server push site:perlmonks.org	[reply]