Windows XP provide three different components, all essentially different implementations of the command-line interface. These three components work similarly, but there are some important differences and limitations.
Command Prompt (cmd.exe)
Commonly known as a DOS box because of its visual and functional likeness to DOS, the Command Prompt window (see Figure 6-1) is the most complete implementation of the command prompt in Windows XP. Any program, GUI or command-line-based, can be started by typing its executable filename at the prompt. In addition, a variety of internal DOS commands (discussed later in this chapter), used primarily for file management, can be executed at the prompt.
If a command-line-based program is launched, it is run in the same window. Many command-prompt applications simply display information and quit; in this case, you'd be returned to the prompt immediately after the program output.
An important distinction between the Command Prompt and the alternatives below is that the Command Prompt maintains context between commands. Each instance of the command interpreter runs in its own virtual machine, each with its own "environment." The environment includes such information as the current directory, the search path (the directories in which the command interpreter looks for the commands whose names you type), and the format of the prompt. Some commands, once issued, change the environment for subsequent commands. The most obvious example of this is when you type a sequence of commands, like this:
C:>cd \stuff C:\Stuff>notepad myfile.txt
This command sequence couldn't be carried out at either the Run prompt or the Address Bar. Since they execute only one command at a time and then exit, the context is lost between each command. Concepts such as "change directory" therefore have no meaning.
But the Command Prompt has limitations as well. Unlike the Address
Bar or Start
Note that Windows XP also includes
Start
Any program can be run by typing its executable filename here, as shown in Figure 6-2, just like in a Command Prompt window. However, in the case of command-line based programs, the context is lost every time a new program is launched. Internal Command Prompt commands, such as CD and DIR, discussed later in this chapter, are not recognized here or in the Address Bar.
Unlike the Command Prompt, you can type a web address (URL) here to open it in the default web browser, or any folder name to open it in an Explorer folder window.
Start
Address Bar
The Address Bar, shown in Figure 6-3, is nearly the functional equivalent of Start
The Taskbar Address Bar can be enabled by
right-clicking on an empty area of the Taskbar and selecting Toolbars
The Address Bar can be enabled in
Windows
Explorer and Internet Explorer by going to View
The various Address Bars differ only in the way folder names and web addresses are handled. If you type a folder name into either Windows Explorer or Internet Explorer, the contents of that folder will be shown in the current window (i.e., no new window will be opened). If a web address, such as http://www.annoyances.org/, is typed into the Taskbar Address Bar or the Windows Explorer Address Bar, that address is opened in the default web browser. If, the other hand, an address is typed into Internet Explorer's Address Bar, the page at that address is opened in IE regardless of the default browser setting.
The main difference between the Address Bar and the Start
http://BigBadaBoom/ and then complain that the
web site doesn't exist. If you type the same text at
the Start