Symbian operating system structure 3: executable files in ROM and Ram

Executable files include EXE and DLL.

* EXE in ROM and Ram
-On the mobile phone, the executable code can be loaded into both the read-only memory (ROM) and the built-in memory or memory card (RAM) of the mobile phone.
-Generally, ROM-based EXE can be directly executed from the Rom.
· Program code and read-only data can be directly read from Rom
· The component only allocates a separate data zone in the ram region for reading/writing data.
-Ram-based EXE is fully executed from Ram
· It contains areas for program code and read-only static data, as well as separate data areas
· If this EXE is run again, the read-only zone is shared, and only the read/write zone needs to be re-allocated.

* DLL in ROM and Ram
-The DLL in the Rom is not loaded into the memory, but directly executed in the Rom.
-The DLL in Ram will be loaded into the memory area of a specific address until all components no longer use the DLL.
-When a DLL is running from Ram, the executable code is determined at the time of loading.
-For static and multi-state DLL, the Code part is shared.