nbd_aio_connect_socket(3)

💅 nbd_aio_connect_socket — bestie's guide to libnbd

okay so real talk, this page is nbd_aio_connect_socket(3) from the LIBNBD manual, and it's genuinely one of the cutest little connectors in the whole library. periodt. let's get into it 🎀

✨ NAME ✨

nbd_aio_connect_socket — connect directly to a connected socket. that's it, that's the whole vibe 🦋

✨ SYNOPSIS ✨

#include <libnbd.h>

int nbd_aio_connect_socket (
      struct nbd_handle *h, int sock
    );

like, literally just hand it a handle and a socket and you're off 💫

✨ DESCRIPTION ✨

okay so this is the begin connecting era of your life — the function starts connecting to the connected socket fd. ngl the parameters behave exactly as documented over in nbd_connect_socket(3), so if you're confused, that's your study material bestie 📚✨

✨ RETURN VALUE ✨

if the call is successful, it returns 0. slay. 🎀

✨ ERRORS ✨

on error, -1 is returned. not slay. 😭

refer to "ERROR HANDLING" in libnbd(3) for how to get further details of the error — like, the actual tea on what went wrong 💀

also heads up: the following parameters must not be NULL: h. for more info see "Non-NULL parameters" in libnbd(3). don't be the person who passes NULL, i'm begging 🙈

✨ NOTES ✨

🌸 Asynchronous connect call 🌸

you can check if the connection attempt is still underway by calling nbd_aio_is_connecting(3) — very much "are we there yet" energy 🚗💨

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 👑

✨ HANDLE STATE ✨

vibe check time — nbd_aio_connect_socket can be called when the handle is in the following state:

• Handle created, before connecting — ✅ allowed (this is your moment 🌈)
• Connecting — ❌ error
• Connecting & handshaking (opt_mode) — ❌ error
• Connected to the server — ❌ error
• Connection shut down — ❌ error
• Handle dead — ❌ error 💀

so like, one (1) state. the rest is a no. iykyk 🫶

✨ VERSION ✨

this function first appeared in libnbd 1.2. a classic, an icon, the moment 👑

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_SOCKET 1

✨ SEE ALSO ✨

go read these, they're literally all connected (pun intended):

• nbd_aio_is_connecting(3)
• nbd_aio_is_negotiating(3)
• nbd_aio_is_ready(3)
• nbd_connect_socket(3)
• nbd_create(3)
• nbd_set_opt_mode(3)
• libnbd(3)

✨ AUTHORS ✨

Eric Blake

Richard W.M. Jones

absolute legends, both of them 🌟

✨ 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

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and that's the whole page bestie 🫶 this was libnbd-1.25.8, dated 2026-10-13, and the page itself is nbd_aio_connect_socket(3). go forth and connect responsibly 💖✨