Working With Ffs Partitions - Symbol PDT 8100 Series Product Reference Manual

PDT 8100 Series Product Reference Guide for Pocket PC 2002
The three FFS Partitions appear as three separate folders in the Windows CE file system
and are as follows:
• Platform: The Platform FFS Partition contains Symbol-supplied programs and
Dynamic Link Libraries (DLLs). This FFS is configured to include DLLs that control
system operation. Since these drivers are required for basic terminal operation,
only experienced users should modify the content of this partition.
• Application: The Application FFS Partition is used to store application programs
needed to operate the terminal. This partition includes the Symbol demo program,
which can be overwritten with your own program.
• Data: The Data FFS Partition is optional and if present contains user data files
generated by your custom programs. The default PDT 8100 image does not
contain a Data FFS partition.

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 cold
boot (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 PDT 8100. Applications stored in the
Application folder are retained even when the terminal is cold booted, just as the PDT 8100
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 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.
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