nbdkit_shutdown, nbdkit_disconnect - request shutdown or client disconnection
#include <nbdkit-plugin.h>
void nbdkit_shutdown (void);
void nbdkit_disconnect (int force);
Plugins and filters can call exit(3) in the configuration phase (before and including .get_ready
, but not in connected callbacks).
Once nbdkit has started serving connections, plugins and filters should not call exit(3). However they may instruct nbdkit to shut down by calling nbdkit_shutdown
, or to disconnect a single client by calling nbdkit_disconnect
.
nbdkit_shutdown
requests nbdkit to shut down asynchronously and returns (note that it does not exit the process immediately).
It ensures that the plugin and all filters are unloaded cleanly which may take some time. Further callbacks from nbdkit into the plugin or filter may occur after you have called this.
nbdkit_disconnect
requests that the current client connection be disconnected. It does not affect other connections, and it does not stop the same client from trying to reconnect.
It is only useful from connected callbacks — that is, after (but not including) .open
, and before .close
. To reject a client in .preconnect
, .open
or .list_exports
you should return an error instead.
If force
is true, nbdkit will disconnect the client immediately, and the client will not receive any response to the current command or any other commands in flight in parallel threads. If force
is false, nbdkit will not accept any new commands from the client (failing all commands other than NBD_CMD_DISC
with ESHUTDOWN
), but will allow existing commands to complete gracefully. Either way, the next callback for the current connection should be .close
.
NBDKit.shutdown : unit -> unit
NBDKit.disconnect : bool -> unit
import nbdkit
nbdkit.shutdown()
nbdkit.disconnect(force)
use nbdkit::*;
pub fn shutdown()
pub fn disconnect(force: bool)
In nbdkit-sh-plugin(3), there are various magic error codes that can be returned to indicate that shutdown or disconnection is needed. See that documentation for a full description.
nbdkit_shutdown
was added in nbdkit 1.20. nbdkit_disconnect
was added in nbdkit 1.34.
nbdkit(1), nbdkit-plugin(3), nbdkit-filter(3).
Eric Blake
Richard W.M. Jones
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