
\Sshl\S:  Example
    
    The following example shows how to create two shells using \Sshl\S.
    Highlighted lines mark the user's input.  First, you type \Sshl\S and a
    carriage return.
    
        \Sshl\S
    
    The \Sshl\S command prints ">>>" which is its prompt.  This prompt shows
    that \Sshl\S is waiting for a command.  On the same line as the prompt,
    you type "create" followed by a name for the new shell and a carriage
    return.
    
        >>> \S create venus \S
    
    The system uses the name you choose for the new shell, that is "venus",
    as the prompt.  You type the commands you want to execute after the prompt.
    If you want to format a file "book.1", you could type:
    
        venus \S mm book.1 > book.1m \S
    
    If you do not want to wait for the file "book.1" to be formatted, you can
    create a new shell layer.  To create a new layer, you type a control
    character and the letter "z" simultaneously.  This moves you out of the
    shell called "venus".  \Sshl\S prompts you again with the three right
    arrows.  They you type "create" followed by the name you choose for the
    second shell.
    
        \S control-z >>> \S create mars \S
    
    \Sshl\S prompts you with the name of the new shell:
    
        mars
   
 
    Now you can execute commands in the shell called "mars" without disturbing
    the command that is executing in "venus".  \Sshl\S prints the name of the
    shell where "book.1" was formatting when it is finished.  In this example,
    \Sshl\S would print "venus".  If you had not redirected the formatted
    version of "book.1", \Sshl\S would have printed the entire file on the 
    terminal screen.  To exit the shell layer called "mars" you type control-z.
    \Sshl\S returns the ">>>" prompt and you type "quit" to terminate the
    \Sshl\S command.  This also deletes the "venus" and "mars" shell layers.
    
        \S control-z \S >>> \S quit \S
