using ftw()

hello

im trying to find more information about the function: ftw()

however it seems every resource has the same thing
how to declare it and what it is supposed to do

does anyone know of a resource that actually has ftw used within a program, so i can get an idea of how to actually use it?

im concerned with such little documentation out there
if i should be using it or if there is a better way to search a directory hierarchy.