cpp/experimental/fs/recursive directory iterator/increment

Advances the iterator to the next entry.

If there are no more entries left in the currently iterated directory, the iteration is resumed over the parent directory. The process is repeated if the parent directory has no sibling entries that can to be iterated on. If the parent of the directory hierarchy that has been recursively iterated on is reached (there are no candidate entries at, is set to an end iterator.

Otherwise, if refers to a directory, it is iterated into if the following conditions are met:


 * disable_recursion_pending has not been called before this increment, i.e..
 * The directory is not a symlink or following symlinks is enabled, i.e.

Exceptions
@1@ if an error occurs. The error code is set to an appropriate error code for the error that caused the failure.

@2@