to paraphrase: during the long upload period your application or the data it uses is in an in-between state such that other users should not be allowed to perform the same or similar operations?

you need either a queue (perhaps) or a lock (definitely). That could be something as simple as creating a lockfile during the upload and deleting it at the end of the processing step: if the lockfile exists, you just warn the other user that they'll have to wait.

You would need a mechanism for dealing with dropped connections, stop buttons and other user problems that might result in the upload being incomplete and the lockfile remaining, though. an age limit for the file would probably be part of that, along with (eg) email notification of the person whose upload failed.

it does sound like perhaps you should reconsider the input mechanism, but without knowing more I can't say anything sensible about that.

In reply to Re: CGI form processing - multiple 'calls' by thpfft
in thread CGI form processing - multiple 'calls' by waris

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.