Subject: Re: Puzzling questions about FFS
To: None <, tech-kern@NetBSD.ORG>
From: Chris Torek <torek@BSDI.COM>
List: tech-kern
Date: 10/28/1994 13:59:54
The synchronous writes in FFS are not intended to make the *data*
fully robust (in the face of system crashes or power failures);
they are to make the *file system structure* fully robust.  That
is, fsck can always tell whether some operation (such as a file
creation/rename/remove/truncate) was completed and, if not, either
complete it or back it out.

For robust data you have fsync and O_SYNC,