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SHELL Statement Details
  Summary  Details  Example                Contents  Index  Back
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 SHELL [commandstring$]
 
 Usage Notes
   ■ SHELL with no commandstring$ gives you a new shell (COMMAND.COM.) You
     then can enter operating-system commands at the prompt. Use the EXIT
     command to return to Visual Basic.
 
   ■ Any .COM file, .EXE file, .BAT program, or MS-DOS command that runs
     under the SHELL statement is called a "child process." Child processes
     are executed by the SHELL statement, which loads and runs a copy of
     COMMAND.COM with the /C option.
 
   ■ The /C option allows any parameters in commandstring$ to be passed
     to the child process. It also allows redirection of standard input
     and output, and execution of built-in commands such as DIR and PATH.
 
   ■ The program name in commandstring$ can have any extension you wish. If
     no extension is supplied, COMMAND.COM looks for a .COM file, then an
     .EXE file, and finally, a .BAT file. If COMMAND.COM is not found, SHELL
     issues the error message, "File not found." Visual Basic does not
     generate an error if COMMAND.COM cannot find the file specified in
     commandstring$, but the operating system will generate an error message.
 
   ■ COMMAND.COM treats any text separated from the program name by at least
     one blank as a program parameter.
 
   ■ Visual Basic remains in memory while the child process is running. When
     the child process finishes, Visual Basic continues.