Regmerge.dll - Symbol PDT 8100 Series Product Reference Manual

Windows CE expects certain files to be in the Windows folder, residing in volatile storage.
Windows CE maintains the System Registry in volatile storage. There are two device
drivers included in the Windows CE image to assist developers in configuring the terminal
following a cold boot: RegMerge and CopyFile.

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 that are in these files 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 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 SDK contains examples of .reg files.
Note: Regmerge only merges the .reg files on cold boots. The merge
process is skipped during a warm boot.
Typically, you should not need to make modifications to registry values for drivers loaded
before Regmerge. However, sometimes during software development, you may need to
modify these values. Since these early loading drivers read these keys before Regmerge
gets a chance to change them, you must warm boot the terminal after a cold boot. 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.
Customizing The Terminal
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