Chapter 1

Appendix 4: Emulator Reference
Overview
As we've seen, the emulator is a vital tool in the Symbian OS software development
process. For non-privileged code, the emulator is almost 100 percent source compatible with
real Symbian OS phones. Many functions that used privileged code on other systems use
servers on Symbian OS, facilitating source code compatibility through the provision of
machine-independent APIs. This means that for the system as a whole, source compatibility
is very high indeed.
The emulator uses Win32 APIs and services to emulate real-machine hardware and
Symbian OS services, including:
� a Windows window to emulate the Symbian OS screen and surrounding machine
fascia,
� the Windows mouse to emulate the Symbian OS pointer,
� the Windows keyboard to emulate the Symbian OS keyboard, plus some control
functions,
� directories in the Windows file system to emulate standard Symbian OS drives,
� PC sound card to emulate Symbian OS sound codec,
� PC communications ports to emulate Symbian OS communications ports,
� Win32 threads to emulate Symbian OS threads,
� a single Win32 process to emulate a single Symbian OS process containing all
Symbian OS threads: this is an important difference between the emulator and a real
Symbian OS phone, which I'll return to later in this appendix,
� a single .exe to include Symbian OS startup code: this is epoc.exe in the case of
any GUI program or a custom .exe for any text console program,
� Win32 DLLs to emulate Symbian OS DLLs, with Win32 DLL search order used instead
of Symbian OS search order,
� Win32 DLLs to emulate Symbian OS server .exes, with Win32 DLL search order used
to find the Win32 DLL,
� the debug window, if active, for debug prints generated by RDebug::Print() (see
e32svr.h).
For C++ development, the emulator's (Figure A4.1) debug build is typically used. Debug
builds contain symbolic information and debugging statements, and the debug emulator
contains useful debugging support such as many debugging keys.