NAME

       nbdkit_shutdown, nbdkit_disconnect - request shutdown or client disconnection

SYNOPSIS

        #include <nbdkit-plugin.h>

        void nbdkit_shutdown (void);
        void nbdkit_disconnect (int force);

DESCRIPTION

       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
       "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
       "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".

LANGUAGE BINDINGS

       In nbdkit-ocaml-plugin(3):

        NBDKit.shutdown : unit -> unit
        NBDKit.disconnect : bool -> unit

       In nbdkit-python-plugin(3):

        import nbdkit
        nbdkit.shutdown()
        nbdkit.disconnect(force)

       In nbdkit-rust-plugin(3):

        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.

HISTORY

       "nbdkit_shutdown" was added in nbdkit 1.20.  "nbdkit_disconnect" was added in nbdkit 1.34.

SEE ALSO

       nbdkit(1), nbdkit-plugin(3), nbdkit-filter(3).

AUTHORS

       Eric Blake

       Richard W.M. Jones

COPYRIGHT

       Copyright Red Hat

LICENSE

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