manual: nftw(); clarify FTW_SLN case
Commit Message
Clarify that if FTW_PHYS is NOT passed, when a dangling symlink is
encountered, the callback can't use the stat info provided.
See: https://bugzilla.redhat.com/show_bug.cgi?id=1422736
@@ -938,7 +938,8 @@ visited and reported. This flag is returned instead of @code{FTW_D} if
the @code{FTW_DEPTH} flag is passed to @code{nftw} (see below).
@item FTW_SLN
The current item is a stale symbolic link. The file it points to does
-not exist.
+not exist. Note that the stat info pointed at by the second argument will
+be undefined in this case.
@end vtable
The last parameter of the callback function is a pointer to a structure
@@ -1087,7 +1088,9 @@ is @math{0} or a bitwise-OR combination of any of the following values.
While traversing the directory symbolic links are not followed. Instead
symbolic links are reported using the @code{FTW_SL} value for the type
parameter to the callback function. If the file referenced by a
-symbolic link does not exist @code{FTW_SLN} is returned instead.
+symbolic link does not exist @code{FTW_SLN} is returned instead. Note
+that if @code{FTW_PHYS} is @emph{not} passed, when @code{FTW_SLN} is
+passed to the callback, the stat data will not be defined.
@item FTW_MOUNT
The callback function is only called for items which are on the same
mounted filesystem as the directory given by the @var{filename}