主题：请教个问题 -- 猫元帅

看看Windows 2000/2003增加的那一大堆Services，好家伙。

一。CP/M和DOS还是有很大距离的，特别是在DOS 2.0以后。

二。Windows用户界面开始是来自OS/2的，而不是来自Mac。

三。Windows NT更多的是Unix发展型而不是VMS。

四。IE可不是抄Netscape，VBScript/JScript和Java Script还是很有不同的。

也就是给专用的64位操作系统和特定应用程序用用而已。

不过你看看游戏的发展速度和内存压力，估计用不了几年，4G内存就悬了。

首先，图形界面（GUI）和鼠标是Mac的首创。

微软和IBM开始一起搞OS/2.搞到一半分了手。后来IBM推OS/2,微软推Winnt 3.X.后来不长时间，微软开始win9x和Winnt 4.0。Windows 1.x/2.x因该在Os/2之前。

Windows 1.0是1985年就推出了，而OS/2 1.0是在1987年12月才推出的！

NT象VMS多些还是象Unix多些？严格的说，都不太像。当时学OS的时候，讨论过这个问题。他们在设计思想上就有很大的不同。

[B]NT and UNIX[/B] 
NT's roots extend back to 1977 and Digital Equipment's release of VMS 1.0. Many core members of the future NT design team left Digital in 1988 to join Microsoft, which released NT's first version, Windows NT 3.1, in 1993. Thus, NT and UNIX have been evolving since the mid-1970s, and trends in academic OS research have influenced each OS. In addition, both OSs have similar design goals: portability, extensibility, and the ability to run on computers ranging from desktop PCs to departmental servers.

Internally, NT is similar to VMS, but how closely do NT's capabilities and features match those of UNIX? Shedding light on this question is difficult, because even the top three UNIX market share leaders--Solaris, HP/UX, and AIX--are in many ways as different from one another as each is from NT. Thus, there is no definitive "UNIX" to compare with NT. Therefore, I'll use traditional or prevalent UNIX features and implementations for each UNIX subsystem in the following comparison of NT and UNIX. I'll draw from the market leaders and three other UNIX variants: Linux, BSD 4.4, and Digital UNIX. 

Unix结构

NT结构

The OS architecture of most versions of UNIX is similar to that of NT. Figure 1 and Figure 2 show the UNIX and NT architectures, respectively. (To explore NT's architecture in depth, see "Windows NT Architecture, Part 1," March 1998 and "Windows NT Architecture, Part 2," April 1998.) Both OS architectures have two modes of operation: user mode and kernel mode. Familiar applications such as word processors and database programs execute in user mode. User mode is nonprivileged, which means that the system restricts programs operating in user mode from directly accessing hardware or resources belonging to other programs. Most of the OS code executes in kernel mode. Kernel mode is privileged, which means that code running in kernel mode can access hardware and resources belonging to any application, with few limitations.

A major difference between UNIX's and NT's architecture is that UNIX does not incorporate its windowing system--the subsystem that manages GUI resources for applications--into kernel mode, as does NT 4.0. Instead, the UNIX windowing system is an add-on user-mode application that its developers wrote using publicly defined UNIX APIs; consequently, third-party products can replace UNIX's windowing system. However, the majority of the UNIX community has adopted MIT's X-Windows as a de facto, if not official, graphical interface standard. Before NT 4.0, the NT windowing system was a user-mode implementation, but Microsoft found that the performance of graphics-intensive applications improved when the windowing system operated in kernel mode.

Another difference between the OS architectures is that UNIX applications can call kernel functions, or system calls, directly. In NT, applications call APIs that the OS environment to which they are coded (DOS, Windows 3.x, OS/2, POSIX) exports. A kernel system-call interface provides APIs for managing processes, memory, and files. The NT system-call interface, called the Native API, is hidden from programmers and largely undocumented. The number of UNIX system calls is roughly equal to the number of Native APIs, around 200 to 300. The API that UNIX applications write to is the UNIX system-call interface, whereas the API that the majority of NT applications write to is the Win32 API, which translates many Win32 APIs to Native APIs.

In the following comparison of NT and UNIX subsystems, I'll contrast the way each OS names internal resources, implements processes and threads, and manages virtual and physical memory. I'll also compare and contrast UNIX's and NT's security model, file-system data caching, networking architecture, and extensibility.
......

如果感兴趣的话，我就说完！

象俺这样的半瓶子趁早一边歇着，看看热闹吧！ …………

再说这也算不上学术之争。都是人家老外发明的东西。我们这些小混混，更本上不了桌面！

Enhanced mode was necessary because DOS did not have the power to access the additional memory Windows needed to run. Windows (from Win3.11to Win98) ran as just another program in DOS, albeit a very powerful program. Fortunately, in the more powerful and later versions of the OS (Windows NT/2000/XP), DOS has been eliminated from the core of the system. As such, Enhanced Mode is no longer applicable for computers using these OSes

顺便把硬盘管理再说明一下

[B][COLOR=blue]NTFS[/COLOR][/B] Windows NT/2000/XP/2003系列Native文件系统
Recommended minimum volume size is approximately 10 MB. Recommended practical maximum for volumes is 2 TB (terabytes). Much larger sizes are possible.Cannot be used on floppy disks.

File size limited only by size of volume

[B][COLOR=blue]FAT[/COLOR][/B]早期DOS系统,现在大多数数码相机，USB移动盘都使用FAT
Volumes from floppy disk size up to 4 GB. Does not support domains.

Maximum file size 2 GB. 

[B][COLOR=blue]FAT32[/COLOR][/B]Windos 9.x系列
Volumes from 512 MB to 2 TB. In Windows 2000, you can format a FAT32 volume only up to 32 GB.Does not support domains.

Maximum file size 4 GB.

问题有些stupid.

一。Windows 3.x中的386增强方式很类似于Windows NT中的内存管理方式。当然到了Windows NT以后，是没有必要再存在那么多的内存管理方式了。

二。Windows 3.x-9.x并不只是DOS Shell，因为它们增加了非常多的功能。正如Novell Netware可以运行在DOS之上，但是我们不能够说Novell Netware只是DOS Shell一样。

我在国内的时候读过一点Windows 3.x的源代码。

一。如果追溯到根的话，应该是Xerox的Star机器，Apple的Mac界面很多也是抄它的。

二。Windows 1.x和2.x的界面有了很大变化。Windows 1.x不过是个Dos Shell，那个界面有些类似后来的Dos 4.0 Shell，而和Mac的区别比较大；Windows 2.x的界面则和OS/2的Presentation Manager很类似。

三。至于WNT是更像VMS还是更像Unix，我看到的书籍里是倾向于后者的。