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<p>
<a href="index.html">tipidee</a><br />
<a href="//skarnet.org/software/">Software</a><br />
<a href="//skarnet.org/">skarnet.org</a>
</p>

<h1> tipidee caveats and FAQ </h1>

<div id="caveats">
<h2> Caveats </h2>
</div>

<h3> <tt>Host</tt> support in HTTP/1.0 </h3>

<p>
 A strict reading of the
<a href="https://datatracker.ietf.org/doc/html/rfc1945">HTTP/1.0 specification</a>
says that the Request-Line is the only piece of client-provided data that can
be used to identify a resource, and that extension headers can modify the
interpretation and processing of that resource but not <em>change</em> what
resource is served.
</p>

<p>
 This goes directly against the use of the <tt>Host</tt> header to identify
the host of a resource and that is used in HTTP/1.1.
</p>

<p>
 A lot of HTTP servers out there don't care about a strict reading of HTTP/1.0
(or even a strict reading of anything, really), and have
historically used <tt>Host</tt> to perform virtual hosting even in HTTP/1.0,
even though it goes against the specification. Consequently, clients have
adapted, and
<a href="https://github.com/curl/curl/issues/5976">even the popular
<tt>curl</tt> client</a> sends a <tt>Host</tt> header in HTTP/1.0.
</p>

<p>
 Since the point of the Web is interoperability, tipidee aligns with
the common practice, and will read a client-provided <tt>Host</tt> header,
if any, to determine what domain the request is directed to, even in
HTTP/1.0 no matter what the spec says. I refer to this practice as
"speaking HTTP/1.05".
</p>

<div id="faq">
<h2> Frequently asked questions </h2>
</div>

<h3> I want my web server to listen to more than one address. Do I need
to do all that for every address I have? </h3>

<p>
 Not necessarily: you could listen to <tt>0.0.0.0</tt> for IPv4, and
<tt>::</tt> for IPv6. But if you don't want your server to listen to
<em>all</em> the addresses on your machine, then yes, you will have
to run one process per address:port tuple.
</p>

<p>
 It's okay though: every listening process is very small. The skarnet.org
server has two network cards and runs a web server on both of them, on
IPv4 and IPv6, over HTTP and HTTPS, which makes 8 services. Plus one
<a href="//skarnet.org/software/s6/s6-log.html">s6-log</a> logger process
for each of these services. Plus a supervisor for every service and every
logger &mdash; for a whooping total of 64 long-running processes just for
its web server functionality; and it's still not even noticeable, the
amount of resources it consumes is negligible. So, don't worry about it;
all your resources are still available for the serving itself.
</p>

<p>
 Note that this allows you to run different instances of
<a href="tipideed.html">tipideed</a>, on different sockets, with different
configurations, if you need it. Use the <tt>-f</tt> option to specify a
different config file in your instances.
</p>

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