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----------------------------------------------------------- From: Absent_Minded_Aquarian Message 6 in Discussion Hi! Correction! NTVDM is running under a protected mode environment, which is the Intel x86 Virtual 8086 emulation mode. This is emulated, not by a software, but by the hardware, i.e., the processor. NTVDM executes native instruction set, of the underlying microprocessor and that is what is also contained in the executing application. This is in contrast with a VES where in the executing application contains the instruction set for the VES, which translates it to the instruction set of the underlying microprocessor. A VES provides a lot of facilities to the executing application: type checking, memory management, security (execution and role), code isolation (execution perspective). NTVDM does no such stuff. In NTVDM, no thunking occurs since the applications that execute undre it are actually written for real mode x86 architecture. Thunking is specific to Windows OS, while real mode x86 is DOS based architecture (no, am not referring to the console like looks, but the architecture of the OS). Thunking is used by Windows to make calls to 16bit protected mode code from 32 bit protected mode code and vice-versa. V86 mode doesnt need to know about the OS since it runs even below the OS: at the microprocessor level. The consuming OS simply toggles a processor bit to enable/disable it. Hope this clears the analogy. Gaurav ----------------------------------------------------------- To stop getting this e-mail, or change how often it arrives, go to your E-mail Settings. http://groups.msn.com/bdotnet/_emailsettings.msnw Need help? If you've forgotten your password, please go to Passport Member Services. http://groups.msn.com/_passportredir.msnw?ppmprop=help For other questions or feedback, go to our Contact Us page. http://groups.msn.com/contact If you do not want to receive future e-mail from this MSN group, or if you received this message by mistake, please click the "Remove" link below. On the pre-addressed e-mail message that opens, simply click "Send". Your e-mail address will be deleted from this group's mailing list. mailto:[EMAIL PROTECTED]
