Windows Server 2008 Server Core : Understanding Internal and External Commands

Some commands don't exist in separate files; they reside in the host program that you use to interact with the computer. The host program for the command prompt is CMD.EXE. If you want to try it out, type CMD and press Enter. You'll see a command prompt. CMD.EXE doesn't end after it opens the command prompt; it remains in the background to receive and react to your keystrokes.

The CMD.EXE file also has a number of internal commands. These special keystrokes tell CMD.EXE to perform a task for you. For example, the Dir command is an internal CMD.EXE command. You won't find Dir listed as an executable anywhere on your hard drive. This book lists all internal commands as commands. Consequently, you'll see the TaskList utility and the Dir command discussed later in the book. If you want to see the full list of commands that CMD.EXE supports, type Help and press Enter. You'll see the list shown in Figure 1 (the list in the screenshot isn't complete—it continues past the bottom of the command window).

Compare the list of commands provided by the Server Core version of CMD.EXE and those provided by other versions of Windows and you'll find some differences. For example, the Server Core version of CMD.EXE doesn't support the AT command (it supports AT as a utility). This makes sense since Server Core doesn't support the Task Scheduler either, since the Task Scheduler is a GUI tool. Most of the changes are additions. Here are the additional commands that CMD.EXE supports (some used to appear as separate utilities) and you'll find all of them discussed in this book.

• BCDEdit
  

• DiskPart
  

• DriverQuery
  

• FSUtil
  

• GPResult
  

• ICACLS
  

• MKLink

• OpenFiles
  

• RoboCopy
  

• SC
  

• SchTasks
  

• Shutdown

• SystemInfo

• TaskList
  

• TaskKill
  

• WMIC
  

Figure 1. CMD.EXE supports a number of additional commands in Server Core.