Here is a FGIO class derived from FGSubsystem that replaces the fgIOInit()
and fgIOProcess() functions. The FGIO::update(double delta) doesn't use the
delta argument yet. I suspect it could be used as a replacement for the
calculated interval value but I'm not familiar enough with that piece of code
just yet.
I've also added two "command properties" to fg_commands.cxx that select the
next or previous view. Writing any value to these properties triggers the
corresponding action. As an example I modified my keyboard.xml:
<key n="118">
<name>v</name>
<desc>Next view</desc>
<binding>
<command>property-assign</command>
<property>/command/view/next</property>
<value type="bool">true</value>
</binding>
</key>
<key n="86">
<name>V</name>
<desc>Prev view</desc>
<binding>
<command>property-assign</command>
<property>/command/view/prev</property>
<value type="bool">true</value>
</binding>
</key>
And of course these actions can also be triggered from external scripts via
the props server.