The kernel can stop any task and start others without help from the application programmer. Windows NT supports preemptive multitasking and threading like most large scale systems. If the administrator loses the login password, the system must be rebuilt. Operating system calls are made with conventional subroutine calls, and a sophisticated system manages users and privileges to meet corporate and defence standards. Win32 replaces the earlier memory allocation scheme with true 32-bit pointers, permitting a 4 gigabyte address space (with 2 gigabytes for application code) exceeded on actual machines only by the 2000s. The Intel 8086 was not a very powerful processor, but the 286 and 386 had features which could support an true multitasking environment. Microsoft had marketed XENIX as a version of UNIX, but it never became very popular as a business operating system. If a program fails to do so, it will stop all other processes on the machine, rendering it inoperable, and this often happened on Win16 machines. A program must do operations quickly and then give control back to Windows, which can then give messages to other tasks. 16-bit Windows is also built around the concept of cooperative multitasking. A user with Windows 95 who does not type in a proper password still can access the local resources, if not the network. DOS was also written to suit the needs of a single user, with minimal security. This was made necessary by the segment-based addressing of the Intel 8086 based processor which essentially adds a 4-bit extension to the 16-bit addressing of the Intel 8080. 16-bit Windows is characterised by the use of 16-bit near pointers, 32-bit far pointers, and an awkward memory allocation system which requires the programmer to lock down a pointer to obtain a physical address and then release it so the operating system can relocate objects as needed to maximise efficiency. MS-DOS uses interrupts to call operating system services. The original version of Windows is a 16-bit GUI program which runs on MS-DOS and was written in Intel 8086 assembler. => Mozilla/4.0 (compatible MSIE 7.0 Windows NT 6.3 WOW64 Trident/8.0. => Sinergi\BrowserDetector\Device Object => Sinergi\BrowserDetector\UserAgent Object => Sinergi\BrowserDetector\Browser Object => For Internet Explorer since version 4.0 and embedded WebBrowser controls (such as Internet Explorer shells, Maxthon and some media players). => mozilla/4.0 (compatible* msie 7.0* *windows*
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