Jeff Garland wrote:
On Tue, 09 Mar 2004 11:36:52 -0500, Beman Dawes wrote
That's an interesting thought. Of course, it might not be another thread but rather another process that created the directory, and that could be a sign of real trouble.
But such a change would allow simpler user code. What is now written:
if ( !exists( foo ) ) create_directory( foo );
becomes:
create_directory( foo );
What happens when the directory existing really does constitute and error, and create_directory() doesn't throw? Will applications fail in difficult to diagnose ways? Can applications protect themselves against silent failure?
How about something like: void create_directory ( const path& name, bool error_if_exists = false);
Then the application can decide -- defaulting to nothrow.
I agree; the application must be able to decide if the directory existing is an error condition or not. However, I don't like the optional argument. I think I would have a hard time remembering whether it was void create_directory(const path& name, bool ok_if_exists = true); or void create_directory(const path& name, bool error_if_exists = false); create_directory(path, true); // ??? Instead I would prefer two separately named functions, like create_directory() and create_directory_exists_ok(). (Well, maybe not these two names exactly, but you get the idea. ;-) ) In the past I've used the word "soft" for this kind of thing: create_directory -- throws if directory already exists soft_create_directory -- doesn't throw if directory already exists
What happens if the path exists but is not a directory? Presumably that case must still throw.
Yes, I think so.
I agree. Just my $0.02. Bob