Re: Copy on write hard links?

From: Rob Landley
Date: Wed Sep 25 2013 - 09:59:41 EST


On 09/24/2013 01:36:56 PM, Thomas Meyer wrote:
Hi,

Is there such a thing?

In the kernel's vfs layer? No, although some filesystems (ala btrfs) do things like that with snapshots.

In userspace? Breaking hardlinks when updating a file is fairly normal, that's why they distinguish between "truncate and rewrite" (preserve hardlinks) and "write new file and rename over old file" (break hardlinks, avoiding the more obvious race conditions).

Rob--
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