Given a "file" structure, the d_path() is a cool function which
gives you the full path of the underlying file. This is what the
/proc/pid/fd code uses to give you the mapping of file descriptors
to real filenames.
And now, dtrace for linux, in the io:::start provider can reflect
the Sun standard structures for buf_t, fileinfo_t etc.
I need to polish off the code, but its looking good - we can see the
full filename of the entity being manipulated and proves the io:::
provider will be most useful for not only writing D scripts, but porting
existing Dtrace utilities (like iosnoop.d)