RFR: 8232861: (fc) FileChannel.force fails on WebDAV file systems (macOS) [v4]

[Brian Burkhalter]

> Apparently `fcntl(fd, F_FULLFSYNC)` can fail with `ENOTTY` in addition to `ENOTSUP` although it is not so documented. The `ioctl()` case is documented as
> [ENOTTY]       fildes is not associated with a character special
>                device.
> [ENOTTY]       The specified request does not apply to the kind of
>                object that the descriptor fildes references.
> 
> This request proposes to catch `ENOTTY` as well and fall back to `fsync(fd)`. The change was verified manually using a WebDAV server and no failures in CI test tiers 1-3 were observed. An alternative would be to fall back to `fsync(fd)` for **all** errors.

Brian Burkhalter has updated the pull request incrementally with one additional commit since the last revision:

  8232861: Remove ENOTSUP fallback for fcntl(fd, F_FULLFSYNC) failure

-------------

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/3366/files
  - new: https://git.openjdk.java.net/jdk/pull/3366/files/0c01b23d..70d518a3

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=3366&range=03
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=3366&range=02-03

  Stats: 19 lines in 1 file changed: 3 ins; 10 del; 6 mod
  Patch: https://git.openjdk.java.net/jdk/pull/3366.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/3366/head:pull/3366

PR: https://git.openjdk.java.net/jdk/pull/3366