nbd_aio_trim(3)                     LIBNBD                     nbd_aio_trim(3)


NAME
       nbd_aio_trim - send trim command to the NBD server

SYNOPSIS
        #include <libnbd.h>

        typedef struct {
          int (*callback) (void *user_data, int *error);
          void *user_data;
          void (*free) (void *user_data);
        } nbd_completion_callback;

        int64_t nbd_aio_trim (
                  struct nbd_handle *h, uint64_t count,
                  uint64_t offset,
                  nbd_completion_callback completion_callback,
                  uint32_t flags
                );

DESCRIPTION
       Issue a trim command to the NBD server.

       To check if the command completed, call nbd_aio_command_completed(3).
       Or supply the optional "completion_callback" which will be invoked as
       described in "Completion callbacks" in libnbd(3).

       Other parameters behave as documented in nbd_trim(3).

       By default, libnbd will reject attempts to use this function with
       parameters that are likely to result in server failure, such as
       requesting an unknown command flag.  The nbd_set_strict_mode(3)
       function can be used to alter which scenarios should await a server
       reply rather than failing fast.

RETURN VALUE
       This call returns the 64 bit cookie of the command.  The cookie is >=
       1.  Cookies are unique (per libnbd handle, not globally).

ERRORS
       On error -1 is returned.

       Refer to "ERROR HANDLING" in libnbd(3) for how to get further details
       of the error.

       The following parameters must not be NULL: "h".  For more information
       see "Non-NULL parameters" in libnbd(3).

HANDLE STATE
       nbd_aio_trim can be called when the handle is in the following state:

        <?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?>
        | Handle created, before connecting   | <?> error                |
        | Connecting                          | <?> error                |
        | Connecting & handshaking (opt_mode) | <?> error                |
        | Connected to the server             | <?> allowed              |
        | Connection shut down                | <?> error                |
        | Handle dead                         | <?> error                |
        <?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?>

VERSION
       This function first appeared in libnbd 1.0.

       If you need to test if this function is available at compile time check
       if the following macro is defined:

        #define LIBNBD_HAVE_NBD_AIO_TRIM 1

SEE ALSO
       nbd_aio_command_completed(3), nbd_can_trim(3), nbd_create(3),
       nbd_set_strict_mode(3), nbd_trim(3), "Issuing asynchronous commands" in
       libnbd(3), libnbd(3).

AUTHORS
       Eric Blake

       Richard W.M. Jones

COPYRIGHT
       Copyright Red Hat

LICENSE
       This library is free software; you can redistribute it and/or modify it
       under the terms of the GNU Lesser General Public License as published
       by the Free Software Foundation; either version 2 of the License, or
       (at your option) any later version.

       This library is distributed in the hope that it will be useful, but
       WITHOUT ANY WARRANTY; without even the implied warranty of
       MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
       Lesser General Public License for more details.

       You should have received a copy of the GNU Lesser General Public
       License along with this library; if not, write to the Free Software
       Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
       02110-1301 USA

libnbd-1.20.0                     2024-05-31                   nbd_aio_trim(3)