This structure contains an array of entities of type PK_FACE_t


typedef struct PK_FACE_array_s
    {
    PK_FACE_t      *array;   --- array of FACEs
    int             length;  --- length of array
    }
    PK_FACE_array_t;

It has the fields:

array:   array of entities of type PK_FACE_t

length:  the number of entities in array