Regmerge.dll - Symbol MC9000-K Product Reference Manual

10-28 MC9000-K/S for Embedded Windows® CE .NET Product Reference Guide

RegMerge.dll

RegMerge.dll is a built-in driver that allows registry edits to be made to the Windows CE Registry.
Regmerge.dll runs very early in the boot process and looks for registry files (.reg files) in certain Flash
File System folders during a cold boot. It then merges the registry changes into the system registry
located in RAM.
Since the registry is re-created on every cold boot from the default ROM image, the RegMerge driver
is necessary to make registry modifications persistent over cold boots.
RegMerge is configured to look in the root of two specific folders for .reg files in the following order:
\Platform
\Application
Regmerge continues to look for .reg files in these folders until all folders are checked. This allows
folders later in the list to override folders earlier in the list. This way, it is possible to override Registry
changes made by the Platforms partitions folders. Take care when using Regmerge to make Registry
changes. The Series 9000 SMDK contains examples of .reg files.
Regmerge only merges the .reg files on cold boots. The merge process is
skipped during a warm boot.
Typically, do not make modifications to registry values for drivers loaded before RegMerge. However,
these values may require modification during software development. Since these early loading
drivers read these keys before RegMerge gets a chance to change them, the mobile computer must
be cold booted. The warm boot does not re-initialize the registry and the early loading driver reads
the new registry values.
Do not use Regmerge to modify built-in driver registry values, or merge the same Registry value to
two files in the same folder, as the results are undefined.