Before this change, nfsmount ignored the --volname flag. After this change, the --
volname flag is respected, making it possible to set a custom volume name.
macOS users should note that Finder will show the correct volume name in most
places, but a notable exception is the sidebar, which will show "localhost".
This seems to be a system limitation (at least without `sudo`), but see the
discussion at https://github.com/rclone/rclone/issues/7503#issuecomment-1933997678
for some possible workarounds.
Before this change, if a user unmounted externally (for example, via the Finder
UI), rclone would not be aware of this and wait forever to exit -- effectively
causing a deadlock that would require Ctrl+C to terminate.
After this change, when the handler detects an external unmount, it calls a
function which allows rclone to cleanly shutdown the VFS and exit.
Before this change, writing files to an `nfsmount` via Finder on macOS would
cause critical errors, rendering `nfsmount` effectively unusable on macOS. This
change fixes the issue so that writes via Finder should be possible.
The issue was primarily caused by the handler's HandleLimit being set to -1. -1 is
the correct default for a NullAuthHandler, but not for a CachingHandler, which
interprets -1 not as "no limit" but as "no cache".
This change sets a high default of 1000000, and gives the user control over it
with a new --nfs-cache-handle-limit flag (available in both `serve nfs` and
`nfsmount`. A minimum of 5 is enforced, as any lower than this will be
insufficient to support directory listing.
- make compile on all unix OSes - this will make the docs appear on linux and rclone.org!
- add --sudo flag for using with mount
- improve error reporting
- fix option handling
Summary:
In cases where cmount is not available in macOS, we alias nfsmount to mount command and transparently start the NFS server and mount it to the target dir.
The NFS server is started on localhost on a random port so it is reasonably secure.
Test Plan:
```
go run rclone.go mount --http-url https://beta.rclone.org :http: nfs-test
```
Added mount tests:
```
go test ./cmd/nfsmount
```
