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 ENVIRON$ (env-variable$)
 ENVIRON$ (n%)
 ENVIRON stringexpression$
 
 Usage Notes
   ■ The following example sets a PATH environment variable:
 
         ENVIRON "PATH=C:\CLIENTS;C:\RATES"
 
   ■ If env-variable$ did not previously exist in the environment-string
     table, it is appended to the end of the table. If env-variable$
     exists in the table when the ENVIRON statement is executed, it is
     deleted, and the new env-variable$ is appended to the end of the table.
 
   ■ If text is a null string ("") or a semicolon (";"), the existing
     parameter is removed from the environment-string table, and the
     remaining body of the table is compressed.
 
   ■ You cannot increase the size of the environment-string table with the
     ENVIRON statement. This means that before you can add a new
     environment variable or increase the size of an existing environment
     variable, you must first delete or decrease the size of existing
     environment variables.
 
   ■ Visual Basic generates the error message "Out of memory" when no more
     space can be allocated to the environment-string table. The amount of
     free space in the table is usually limited.
 
   ■ The environment variable must be expressed in all uppercase letters. For
     example:
 
         This Statement...           Has This Effect...
         ═══════════════════════     ═══════════════════════════════════════
         ENVIRON "PATH=C:SALES"      Changes the path
 
         ENVIRON "path=C:SALES"      Does not change the path; creates a new
                                     environment variable that cannot be used
                                     by the operating system
 
   ■ MS-DOS discards the environment-string table modified by the ENVIRON$
     function when your program ends. The environment-string table is then
     the same as it was before your program ran.
 
   ■ You can use this statement to change the PATH parameter for a "child"
     process (a program or command started by a SHELL statement) or to pass
     parameters to a child by creating a new environment variable.
 
   ■ If you specify an environment-string name, but it cannot be found
     in the environment-string table, or there is no text following it,
     then ENVIRON$ returns a null string. Otherwise, ENVIRON$ returns
     the text following the equal sign in the environment-string table.
 
   ■ If you specify a numeric argument (n), the nth string in the
     environment-string table is returned. In this case, the string
     includes all of the text, including environmentstring$. If the nth
     string does not exist, ENVIRON$ returns a null string. The n argument
     can be any numeric expression; it is rounded to an integer.