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─────C/C++ Language─────────────────────────────────────────────────────────
 
     A Microsoft extension allows the last member of a C or C++
     structure or class to be a variable-sized array. These are called
     unsized arrays. The unsized array at the end of the structure
     allows you to append a variable-sized string or other array, thus
     avoiding the run-time execution cost of a pointer dereference.
 
     For example, you can declare the following:
 
          struct PERSON
          {
              unsigned number;
              char     name[];    // Unsized array
          };
 
     If you apply the sizeof operator to this structure, the ending
     array size is considered to be 0. The size of this array is 2
     bytes, which is the size of the unsigned member. To get the true
     size of a variable of type PERSON, you would need to obtain the
     array size separately.
 
     The size of the structure is added to the size of the array to
     get the total size to be allocated. After allocation, the array
     is copied to the array member of the structure, as shown below:
 
          struct PERSON *ptr;
          char who[40];
 
          printf( "Enter name: " );
          gets( who );
 
          // Allocate space for structure, name, and terminating null
          ptr = malloc( sizeof( struct PERSON ) + strlen( who ) + 1 );
 
          // Copy the string to the name member
          strcpy( ptr->name, who );
 
     Even after the structure variable's array is initialized, the
     sizeof operator returns the size of the variable without the
     array.
 
     Structures with unsized arrays can be initialized, but arrays
     of such structures cannot be initialized. For example:
 
          struct PERSON me  = { 6, "Me" };        // Legal
          struct PERSON you = { 7, "You" };
 
          struct PERSON us[2] = { { 8, "Them" },  // Error
                                  { 9, "We" } };
 
     An array of characters initialized with a string literal gets
     space for the terminating null; an array initialized with
     individual characters (for example, {'a', 'b', 'c'}) does not.
 
     A structure with an unsized array can appear in other structures,
     as long as each is the last member declared in its enclosing
     structure. Classes or structures with unsized arrays cannot have
     direct or indirect virtual bases.
                                    -♦-