This section provides a simple introduction to the vnode interface. The information herein is gathered from pivotal papers on the subject [Kleiman86,Rosenthal90] and from system C header files -- specifically <sys/vfs.h> and <sys/vnode.h>.
The two important data structures used in the vnode interface are struct vfs and struct vnode, depicted in Figures fig-vfs-h and fig-vnode-h, respectively.