a utility written using PSGI and Perl where the author lamented having to write additional scripts to ensure the services were running.

Same problem as with almost any setup where webserver and applications run on in different processes. PSGI is perl-specific, FastCGI is not. FastCGI keeps your application running in an isolated process, so crashing the webserver does not kill the application, and crashing the application does not kill the webserver. Getting the application process running is a problem.

You could start it manually. Every time your application crashes.

You could construct something crazy, involving hand-started scripts, cron jobs, and I don't know what else to start the application process.

Or you could make starting your application a problem for the operating system. After all, it is able to start the webserver without manual intervention, so it can do the same to your application. (With daemontools and runit, you simply need a shell script to invoke your application. With systemd, you write an INI-style configuration file to do the same job in a much more complicated way. With a classic init system, you set up a daemon by an init script, or invoke it directly from init. On Windows, you need to set up a service.)

Apache also offers mod_fcgid to manage your FastCGI application process(es) for you, instead of using operating system services. Other webservers might offer similar modules. This has the advantage that you don't need to keep the application process(es) running if there are no requests for them. The disadvantage is that they are not as isolated from the webserver as a process started as an independant daemon started by init, daemontools, runit, or systemd.

Alexander

--
Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)

In reply to Re^3: CGI Header Breaks on Second AJAX Call by afoken
in thread CGI Header Breaks on Second AJAX Call by brandon8696

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.