Doug, That will work, but you should also consider what would happen if another web user requests this service while it is processing another request. There are a lot of way to handle that situation. The way we normally do this is to setup a unique session cookie that would contain a name that could be used as a file name or directory name to keep the multi-user environment separate. We normally do this for other reasons anyway, but you do not need to use cookies. Your CGI could just use the API call to generate a GUID (Guaranteed Unique IDentifier) which could then be used as a file name. That file name would be the name used for both the status file and the output file.
Another thing to point out is that when your status page autorefreshes, it does not need to point to your CGI each time. It could work just as you describe, but I would probably use the simpler approach of having your initial CGI write out the status page to the same file name that will eventually contain the final output. This status page would contain the autorefresh tag. The spawned process that does the work would write its output to another file and when finished, it would delete the status page file and rename its output file to the same name as the status page. That way, the page the client is autorefreshing will "instantly" become the output page whenever the processing is complete. Finally, you need to have a way to automatically clean up all these output files. We normally do this with another process that is running on the web server and automatically deletes all files older than a certain age. You could also do this in the process that you spawn to do the processing if you are using a hosting service and do not have access to the server, so that every time you run the process, it first deletes all output files that are more than 20 minutes old (or whatever criterion you choose). Glenn Lawler www.incodesystems.com -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Doug Hale Sent: Tuesday, July 06, 2010 1:20 PM To: [email protected] Subject: Re: [delphi-en] Prevent CGI interface timeout. Ok, I'm a little slow today, but I think I've figured out what you all are trying to tell me. 1) check to see if the work is already in progress if not 2) ShellExecute another program to do the actual work 3) return an initial page with the wait message to the user and the autorefresh if so 2) see if the work is done if not 3)return another message or partial results and autorefresh if so 3) return the results This should work, thanks Doug autorefresh - is that <meta http-equiv="refresh" content"30"> for a 30 second wait. ------------------------------------ ----------------------------------------------------- Home page: http://groups.yahoo.com/group/delphi-en/ To unsubscribe: [email protected]! Groups Links
