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From: Gerd Hoffmann <kraxel@redhat.com>
Date: Fri, 13 Nov 2015 13:34:35 +0100
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Subject: Re: [Qemu-devel] [PATCH v2 3/4] usb-mtp: Add support for inotify
 based file monitoring
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To: Bandan Das <bsd@redhat.com>
Cc: qemu-devel@nongnu.org

  Hi,

> +            switch (mask) {
> +            case IN_CREATE:
> +                if (event->mask & IN_ISDIR) {
> +                    /*
> +                     * Add the watchpoint first so we
> +                     * don't miss events in this subdir
> +                     */
> +                    name = g_strndup(event->name, event->len);
> +                    path = g_strdup_printf("%s/%s", parent->path, name);
> +
> +                    watchfd = usb_mtp_add_watch(s->inotifyfd, path);
> +                    g_free(path);
> +                    g_free(name);
> +
> +                    if (watchfd == -1) {
> +                        continue;
> +                    }
> +                }

So, to follow up my mail from today in the morning:

I think this is not needed here ...

>          usb_mtp_object_readdir(s, o);
> +        if (usb_mtp_inotify_mon(s, o)) {
> +            fprintf(stderr, "usb-mtp: adding watch for %s failed\n", o->path);
> +        }

... but here we have to add the watch first, then read the directory.
When reading the directory first we'll miss new files which are added
after readdir() but before add_watch().

cheers,
  Gerd