On Wed, 2011-02-09 at 11:29 -0500, Dave Abrahams wrote:
At Wed, 9 Feb 2011 09:15:24 -0500, Beman Dawes wrote:
recursive_directory_iterator currently always follows directory symlinks [...] Thus I'd like to add an option to either following directory symlinks or not. Which should the default be? It might take extra logic on the user's part to avoid infinite recursions in a case where a directory symlinks an ancestor, so maybe it would make sense to have symlink-following be an explicit choice.
I agree with Dave. Existing code *might* have been written with all the code that checks for loops and escaping from a local tree. But... Having written code using the recursive_directory_iterator (on Windows XP), I know for a fact that I have never taken account of the fact that it might happen because on that platform: it just isn't an issue that is ever going to occur. On *nix, my mindset has been coloured by the default behaviour of commands that process directories: they don't follow symlinks unless you tell them to, so I've implicitly assumed (incorrectly) that's what any recursive directory iterator would do. Coding to safely handle automatically following of symlinks on a recursive directory scan is sufficiently annoying that I'd suggest: (a) most people haven't done it (properly); and (b) adding an extra flag when it is to be done is a good reminder that the code is going to need to be more complex. As long as the change is documented in the release notes, I'd have thought that would be sufficient. Phil -- Phil Richards, <news@derived-software.ltd.uk>