Re: [MacPerl] Troublesome CGIs

[David Steffen <steffen@biomedcomp.com>]

Peter:

In reply to:

>Problem:
>After some random time (anything from seconds to hours) some, or all, of
>the cgi "applications" will hang.

Based on the MacPERL CGI documentation, discussion on this list, and a fair
bit of personal experience, my understanding is as follows:

You cannot have more than one CGI (or ACGI; for the purposes of this
discussion I believe them to be equivalent)  running at the same time.
This is purported to be due to the fact that MacPERL is not multithreading.
(It seems to me that this might be cured, or at least made more tolerable
in the CGI glue, but until I have done it, I can't say for sure.)  The
consequences are what I find to be an extreme limitation in using MacPERL
to write CGI's: you must never have one person hit a MacPERL CGI while
another (or the same) MacPERL CGI is running.  How can you guarantee that?
As far as I know, you can't.

Thus, the idea I suggest you explore is that a hang results when someone
hits one of your ACGI's while a previous one is running.  I have found the
QPQ responds to this less gracefully than WebSTAR, by the way.  In my hands
a second hit would bring down the computer under QPQ, whereas under
WebSTAR, the second hit would merely be ignored.

I have not yet implemented a satisfactory solution.  The best short term
idea I have is to write the ACGI in AppleTalk, and have your AppleTalk
script invoke a Perl script (plain text, not a CGI) to do all the work.

-David Steffen-

David Steffen, Ph.D.
President, Biomedical Computing, Inc. <http://www.biomedcomp.com/>
Phone: (713) 610-9770 FAX: (713) 610-9769 E-mail: steffen@biomedcomp.com



***** Want to unsubscribe from this list?
***** Send mail with body "unsubscribe" to mac-perl-request@iis.ee.ethz.ch