VFS_SYNC(9) on FreeBSD

The text dcd199264694, as FreeBSD 2.2.8-RELEASE, FreeBSD 2.2.7-RELEASE, FreeBSD 2.2.6-RELEASE, FreeBSD 2.2.5-RELEASE, FreeBSD 2.2.2-RELEASE shipped it.

flush unwritten data

VFS_SYNC(9) on FreeBSD now