Hello, I'm working on an web application that basically allows a user to download files stored locally on the server. There is more security than that but that is the general idea. There are multiple users that access the system and can potentially be accessing the same files right around the same time. Below is a highly simplified sample of the code

use CGI;
my $q = CGI->new;

my $file = '/home/somelocation/somefile.pdf';

   
open(MYFILE,$file) or return(0);


print $q->header(-type            => 'application/pdf',
   );

   binmode (MYFILE);
   binmode(STDOUT);

   {local $/; print <MYFILE>}
   close MYFILE;

[download]

What I am trying to do is add decryption to the process. I'm thinking I'd write a script to encrypt all the files. Then I'd like to modify the code above so that as a user tries to download the file, it is decrypted and the user can save the file. How can I do this. Again, multiple people may be accessing the same file and the files may be very large. Any help would be greatly appreciated. TIA

MPM

In reply to Encrypt files on server and then decrypt when user downloads by MPM

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