nptr

    A pointer to the wide-character string to be converted to a long
    integer.

 endptr

    The address of an object where the function can store a pointer
    to the first unrecognized character encountered in the conversion
    process (the character that follows the last character processed
    in the string being converted). If endptr is a NULL pointer, the
    address of the first unrecognized character is not retained.

 base

    The value, 2 through 36, to use as the base for the conversion.

    If base is 16, leading zeros after the optional sign are ignored,
    and 0x or 0X is ignored.

    If base is 0, the sequence of characters is interpreted by the
    same rules used to interpret an integer constant. After the
    optional sign:

    o  A leading 0 indicates octal conversion.

    o  A leading 0x or 0X indicates hexadecimal conversion.

    o  Any other combination of leading characters indicates decimal
       conversion.