Re: [Libguestfs] [PATCH libnbd] examples: Include an example of integrating with the glib main loop.

> +static gboolean > +prepare (GSource *sp, gint *timeout_) > +{ > + struct NBDSource *source = (struct NBDSource *) sp; > + > + /* When the NBD handle moves out of the created state (which means > + * that it first has a socket associated with it) we must initialize > + * and register the pollfd. > + */ > + if (!source->poll_registered && !nbd_aio_is_created (source->nbd)) { > + int fd; > + > + if (source->connecting_callback) { > + DEBUG (source, "calling connecting_callback"); > + source->connecting_callback (source); > + } If I understand nbd_aio_connect_tcp properly, there are cases where we end up trying several options presented from getaddrinfo() with a possible reset back to START, at least until we get an fd that sticks. Does this need to take into account that an fd might change while still trying to do the initial connect?

> + /* Run the main loop until quit. */ > + g_main_loop_run (loop); > + exit (EXIT_SUCCESS); I guess the condition for causing the main loop to run is later on in one of the callbacks?

> +/* This callback is called from libnbd when any read command finishes. */ > +static int > +finished_read (void *vp, int64_t cookie, int *error) > +{ > + size_t i; > + > + if (gssrc == NULL) > + return 0; > + > + DEBUG (gssrc, "finished_read: read completed"); > + > + /* Find the corresponding buffer and mark it as completed. */ > + for (i = 0; i < nr_buffers; ++i) { > + if (buffers[i].cookie == cookie) > + goto found; > + } > + /* This should never happen. */ > + abort (); > + > + found: > + buffers[i].state = BUFFER_READ_COMPLETED; You asked on IRC if we should change the semantics of the *_callback variants to auto-retire the command (right now, the commands are not retired until nbd_aio_command_completed, but you can't call that from this callback because of the nbd handle lock - and calling it shouldn't reveal any more information than what you already have access to here). That may be a good idea to play with.