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VARPTR and VARSEG return the address of a variable (for numeric variables)
or the address of a string descriptor (for near string variables).
 
VARPTR(variablename)
VARSEG(variablename)
     ■ The argument variablename can be any BASIC variable, including a
       record variable or record element.
 
Usage Notes
    ■ When variablename is a numeric variable, the VARPTR function returns
      an unsigned integer (the offset of the variable within its segment).
    ■ When variablename is a numeric variable, the VARSEG function returns
      an unsigned integer (the segment address of the variable).
    ■ When variablename is a string variable, VARSEG returns the segment
      address of the variable, and VARPTR returns the offset address of
      the variable.
    ■ If variablename is not defined before VARPTR or VARSEG is called,
      the variable is created and its address is returned.
    ■ VARPTR and VARSEG are often used with Absolute, BLOAD, BSAVE,
      Interrupt, PEEK, POKE, or when passing arrays to procedures written
      in other languages.
 
Note on Mixed-Language Programming
    ■ Do not pass expanded memory arrays to non-BASIC procedures. (If
      you start QBX with the /Ea switch, any of these arrays may be stored
      in expanded memory:
        -  Numeric arrays < 16K in size
        -  Fixed-length string arrays < 16K in size
        -  User-defined-type arrays < 16K in size
    ■ If you want to pass arrays to non-BASIC procedures, first start QBX
      without the /Ea switch. (Without the /Ea switch, no arrays are
      stored in expanded memory.)
    ■ For more information on using expanded memory, see
      ◄Using Expanded Memory►.
 
Usage Notes
    ■ When using VARPTR or VARSEG to get the address of an array, use the
      first element of the array as the argument:
 
        DIM A(150)
        .
        .
        .
        ArrAddress=VARPTR(A(1))
 
    ■ You can use VARPTR alone to get the address of a numeric variable
      stored in DGROUP. You must use both VARPTR and VARSEG to get the
      complete address of a numeric variable stored in far memory.
    ■ It is not meaningful to use VARSEG and VARPTR for far strings, since
      the format of the far strings' string descriptor is different from
      the string descriptor for near strings. See the ◄StringAddress► for
      routine information on locating the address of a far string's
      string descriptor.
    ■ You cannot use VARPTR to get the address of a file's buffer.
      Use the FILEATTR function to get information about a file.
    ■ Programs written in earlier versions of BASIC that used VARPTR to
      access numeric arrays may no longer work. You must now use a
      combination of VARPTR and VARSEG. For example, the following
      QuickBASIC version 3.0 fragment no longer works correctly:
 
        DIM Cube(675)
        .
        .
        .
        BSAVE "graph.dat",VARPTR(Cube(1)),2700
 
      The fragment could be rewritten as follows to work in the current
      version of BASIC:
 
        DIM Cube(675)
        .
        .
        .
        ' Change segment to segment containing Cube.
        DEF SEG=VARSEG(Cube(1))
        BSAVE "graph.dat",VARPTR(Cube(1)),2700
        ' Restore BASIC segment.
        DEF SEG
 
    ■ The VARSEG function, combined with VARPTR, replaces the PTR86
      subprogram used in previous versions of BASIC.
 
Programming With OS/2 Protected Mode
    ■ The VARSEG function returns the selector of the specified variable
      or array.
 
Important
    ■ Because many BASIC statements move variables in memory, use the
      values returned by VARPTR and VARSEG immediately after the functions
      are used.