Rockwell Automation 2727-MRSDK MobileView Terminals Software Development Kit User Manual - Manual (Page 12)

Publication 2727-UM004B-EN-P - February 2004
1-6 Introduction to the MobileView SDK
keys for control panel applets and other operating system items will
be maintained even in the case of operating system upgrades.
On the other hand, the priority given to persistent registry information
over default operating system registry information makes it possible
for applications or users to cause problems with operating system
startup by changing the wrong registry keys. When manipulating the
CE Registry applications, users should exercise the same degree of
caution that would be required in the case of a Windows 9x or NT
device.
Policies for When Registry Flushing Occurs
Control panel applets supplied with the operating system have been
customized to automatically flush the registry upon exiting the applet.
This allows users to change typical control panel settings such as
network, device name, screen saver, etc. and have these be flushed
without having to manually issue a registry flush to save these. Since
the flush occurs on applet exit as an optimization, users just need to
remember to close the applet after making changes for the automatic
flush to occur. Due to the inner workings of the applets, it is not
feasible to only flush on applet close if a value was changed, so a
flush occurs on applet close even if no registry values were actually
altered.
Other applications such as Internet Explorer, remote networking, and
any third-party packaged applications are not customizable in this
fashion and hence changes they make to the registry will not be
persistent until some other application flushes the registry. To address
this, two features of the operating system are present.
First, an executable regflush.exe supplied with the system may be
manually executed by a user at any time to flush the registry to
persistent storage; this application simply calls RegistryFlush().
Second, upon a controlled shutdown requested by an application
through the power/shutdown driver results in an automatic flush of
the registry after applications have signaled that their cleanup is
complete and before the hardware is actually shutdown or reset.
During an uncontrolled shutdown (i.e. hard-power down), the system
does not have enough time to flush the registry to persistent storage.
IMPORTANT
Since some applications and drivers only read the
Registry at start-up, some registry changes made by
applications will have no effect until the terminal is
re-started.