Returns the size (in bytes) of all files recursively found in @c dir or
@c wxInvalidSize in case of error.
- In case it happens that while traversing folders a file's size can not
+ In case it happens that while traversing folders a file's size cannot
be read, that file is added to the @a filesSkipped array, if not @NULL,
and then skipped. This usually happens with some special folders which
are locked by the operating system or by another process. Remember that