Working With Ffs Partitions; Regmerge.dll - Symbol PDT 8000 Series Product Reference Manual

Working with FFS Partitions

Because the FFS partitions appear as folders under the Windows CE file system, they can
be written to and read like any other folder. For example, an application program can write
data to a file located in the Application folder just as it would to the Windows folder.
However, the file in the Application folder is in non-volatile storage and is not lost on a hard
reset (e.g., when power is removed for a long period of time).
Standard tools such as ActiveSync can be used to copy files to and from the FFS partitions.
They appear as the "Application," "Platform," and "Data" folders to the ActiveSync explorer.
This is useful when installing applications on the terminal. Applications stored in the
Application folder are retained even when the terminal is hard reset, just as the PDT 8000
Demo program is retained in memory.
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 hard reset: 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 hard reset. 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 hard reset from the default ROM image, the
RegMerge driver is necessary to make registry modifications persistent over hard resets.
Regmerge is configured to look in three specific folders for .reg files in the following order:
\Platform
\Application
\Data
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 hard resets. The merge
process is skipped during a soft reset.
Customizing the Terminal
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