dlopen man page is present in foreign language man-pages but not in english. it's just plain missing...
This was fixed in November... take a look at the current man-pages rpm in Rawhide (the latest one, probably not yet in Rawhide but coming soon, is 1.34-1... but this has been part of man-pages since the 1.31-something)
*** Bug 30326 has been marked as a duplicate of this bug. ***