I agree, it sounds like Anonymous Monk
is looking for a solution that would best encompass both client-side and server-side routines - However, for basic upload size determination, the CONTENT_LENGTH
environment variable can be used to find the size of the POST
component of the multi-part request - This approach has merit where the server-side application may need to manipulate the uploaded file via a process where there are subsequent limits on file size. It should also be noted to that this is the same way by which CGI.pm
size restrictions as set by the $CGI::POST_MAX
An example as to how one can make use of the CONTENT_LENGTH environment variable to impose custom handling of over-size multi-part requests can be found here.