The MDB file systems debugging support includes a built-in facility to convert vnode pointers to the corresponding file system path name. This conversion is performed using the Directory Name Lookup Cache (DNLC); because the cache does not hold all active vnodes, some vnodes might not be able to be converted to path names and "??" is displayed instead of a name.
Display a table of mounted file systems, including the vfs_t address, ops vector, and mount point of each file system.
Display a table of vnodes with active network locks registered with the lock manager. The pathname corresponding to each vnode is shown.
Display the pathname corresponding to the given vnode address. If the -v option is specified, the dcmd prints a more verbose display, including the vnode pointer of each intermediate path component.
Iterate over the set of active block I/O transfer structures (buf_t structures). The buf structure is defined in <sys/buf.h> and is described in more detail in buf(9S).