nbd_aio_connect_command3

Usage

 #include <libnbd.h>
 int nbd_aio_connect_command (
       struct nbd_handle *h, char **argv
     );

Overview

Run the command as a subprocess and begin connecting to it over stdin/stdout. Parameters behave as documented in nbd_connect_command(3).

You can check if the connection attempt is still underway by calling nbd_aio_is_connecting(3). If nbd_set_opt_mode(3) is enabled, the connection is ready for manual option negotiation once nbd_aio_is_negotiating(3) returns true; otherwise, the connection attempt will include the NBD handshake, and is ready for use once nbd_aio_is_ready(3) returns true.

Return value

If the call is successful the function returns 0.

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", "argv". For more information see "Non-NULL parameters" in libnbd(3).

Handle state

nbd_aio_connect_command can be called when the handle is in the following state:

 ┌─────────────────────────────────────┬─────────────────────────┐
 │ Handle created, before connecting   │ ✅ allowed              │
 │ Connecting                          │ ❌ error                │
 │ Connecting & handshaking (opt_mode) │ ❌ error                │
 │ Connected to the server             │ ❌ error                │
 │ 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_CONNECT_COMMAND 1