how to keep tracking the system command in cgi

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

Hi monks,
In my cgi script,
After creating a directiory,I have to run a seperate perl script,this script does some manipulation and installation.Also moves some files to that directory.
when a user tries to abort the execution, pressed stop or refresh button,i need to check the status of running perl script....
I need to delete the created folder if aborted or stopped for other user to access...

Note:I dont have rights to restrict the user and disable of IE buttons etc...

Please throw some lights how to solve this issue..

Thanks in advance.....

Comment on how to keep tracking the system command in cgi

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Re: how to keep tracking the system command in cgi by serf (Chaplain) on Feb 10, 2006 at 12:07 UTC
If the user clicks the Stop button it will not stop the CGI script from running - it just stops the browser waiting for a reply from the webserver. Once the CGI program is launched it's launched, it doesn't sit there waiting to see if the client still wants an answer - it just goes away and does its job and hands the results back to the webserver to pass back to the client when it's done. There isn't any way for the user to stop the script from running - short of making another script specially for killing the first script (or some such functionality added to the first script).	[reply]
Re^2: how to keep tracking the system command in cgi by misterb101 (Sexton) on Feb 10, 2006 at 14:31 UTC
Well there is a way of doing this (there's always a way of doing it! ;) But this would involve forking off the installation process and using IPC or another method to communicate with the forked process. Is this what you are looking for? if so, consult the 'perldoc perlfork' page. There is however a limitation when used on a non-linux system like windows that doesn't support the fork system call. Good luck! Cheers, Rob	[reply]
Re: how to keep tracking the system command in cgi by samizdat (Vicar) on Feb 10, 2006 at 17:05 UTC
You can run a `ps -ax` command and `grep` for your command's name in the returned output. You could also, if you need intermediate results, write (or append) progress indicators to a log file and check that file's contents. For example, Create Directory... write 'S1' to log file Write First File... write 'S2' to log file Write 2nd File... write 'S3' to log file Write last File... write 'Sx' to log file Read the file and RegEx for /Sx/. Some variant of this should help you. You could also use a SHM drop-box or other in-memory variant. Don Wilde "There's more than one level to any answer."	[reply] [d/l] [select]