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please wait message - tell browser to begin opening page so wait message is displayed right away. . .

hello,

I have cgi which accesses a very large datafile, does some processing and displays the results. I set up a wait message for this page using the method shown below (see waitpage method).

The Problem: the browser does not want to start loading the page (which includes the wait message) until the script is almost finished processing (or perhaps it is waiting for a certain amount of data to be returned before it starts rendering to the next page.)

I have bypassed this problem by cheating and printing a bunch of spaces before the cgi does the bulk of the processing. This works, but then of course, it is a waste of time, and it puts a bunch of spaces in the html page source.

Can someone point out the correct way to do this?

thanks!

waitpage method:
----------------------------------------------------------------------------------------------
#!/usr/bin/perl

wait_header();

#access database
(some code here);
#process data
(more code here);
#print results
(more code here);

wait_footer();

sub wait_header{

print "Content-type:text/html\n\n";
print qq{
<html>
<head>
<title>Please Wait...</title>

<Script>
function showContent() {
document.getElementById("wait").style.display = "none"
document.getElementById("content").style.display = "block"
window.document.title = "Finished";
}
</Script>
</head>
<body onLoad="showContent()">

<div id=wait>
<h3>Accessing Database<h3>
<p>Please wait . . .</p>
<img src="waitbar.gif">
</div>

<div id="content" style="display:none;">
};
}

sub wait_footer{
print qq{
</div>
};
html_footer();
}

SOLUTION