Perl session and headers

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

Hello,

I'm having trouble with an assignment, the teacher required me to create a login session program in one single CGI program, basically one big if else program. Firstly I have this bit of code at the top of the page:

# Check cookie and initialise a guest session if need be
$sid = $q->cookie("CGISESSID") || undef;
$session = new CGI::Session("driver:File",$sid,{'Directory'=>"./tmp/se
+ssions"});
print $session->header();
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Which basically creates a guest session, even though I'd prefer no session be created unless the user logs in, but regardless it works.

Later on I have another bit of code within the same document to display a picture:

print "Content-disposition: attachment; filename=$qstring\n";
print "Content-type: image/jpg\n\n";
open IMG, "<restricted/$qstring";
flock IMG, 1;
while (sysread(IMG, $buf, 512) > 0) {
        print $buf;
}
flock IMG, 8;
close IMG;
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However all this does when it's ("Executed") is display the binary file simply because the header is already set from the session, thus it will never open the image.

Is there anyway I can deal with this situation? perhaps change the header (if it's possible) or perhaps a way to check if a session exists without creating a header?

Thank you!

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Re: Perl session and headers by Anonymous Monk on Jun 06, 2011 at 08:24 UTC
See CGI::Session "cache" issue, same problem, same answer. When you get tired of reinventing wheels, start over with Catalyst, it is a fully electric 4wd flying chainsaw	[reply]
Re: Perl session and headers by locked_user sundialsvc4 (Abbot) on Jun 06, 2011 at 10:18 UTC
Since this is an assignment, it is extremely important that you get your teacher involved in your question, and that you do so as soon as possible. Here’s why: the class’s ultimate responsibility to each other, and to/with the teacher, is to see to it that “everybody learns the material, together.” You have a part in that. If you are having trouble with an assignment, so, undoubtedly, is everyone else. Who needs to know about that first? The teacher. (I know ... I am one, sometimes.) And so, as the difficulties are worked through – as learning takes place – it can occur where it properly should ... in your classroom. Teachers can’t read minds, even though they sometimes seem to. Yeah, learning this stuff is difficult ... and, I warn you, it never really gets any easier. But, keep the learning process centered in the classroom.
Re^2: Perl session and headers by Argel (Prior) on Jun 07, 2011 at 20:16 UTC
It's up to each student to determine how best they can learn the subject matter. And using a real-world problem solving approach -- i.e. finding the best books, online resources, etc. -- seems perfectly reasonable to me. And given that teachers are not be on-call 24/7 alternative approaches are a necessity. Elda Taluta; Sarks Sark; Ark Arks My deviantART gallery	[reply]
Re^2: Perl session and headers by Anonymous Monk on Jun 06, 2011 at 10:37 UTC
blah blah blah, everything after the header is content -- only one set of headers	[reply]