? - List the internal commands

 Purpose:    Display a list of internal commands or, prompt for a command. 
             
             
 Format:     ? ["prompt " command ] 
             
             prompt :  Prompt text about whether to execute the command. 
             command :  Command to be executed if user answers Y 
 

 Usage 

 ? has two functions.  When you use the ? command by itself, it displays a 
 list of internal commands.  If you have disabled a command with SETDOS 
 /I, it will not appear in the list. 

 The second function of ? is to prompt the user before executing a 
 specific line in a batch file.  If you add a prompt and a command, ? will 
 display the prompt followed by "(Y/N)?" and wait for the user's response. 
  If the user presses "Y" or "y", the command line will be executed.  If 
 the user presses "N" or "n", the command line will be ignored. 

 For example, the following command might be used in a batch file: 

 
         ? Load the network call netstart.btm
 

 When this command is executed, you will see the following prompt; if you 
 answer "Y", the CALL command will be executed: 

 
         Load the network (Y/N)?