failure using wpa_supplicant from command line

Jouni Malinen j at
Sat Sep 17 10:19:24 PDT 2016

On Fri, Sep 02, 2016 at 02:52:00PM +0300, Gucea Doru wrote:
> I further investigated the problem and discovered that the scanning
> process is not started because wpa_supplicant times-out on a netlink
> socket.
> Strace shows me that there is a timeout on a pselect call with EAGAIN
> ( For reference I also attach lsof
> output (

Where do you see EAGAIN there?

> Could someone help me to identify what is the expected input for this
> socket and why the socket times out?

I'm not sure I've understood what you describe as an issue here.. The
eloop pselect calls are expected to time out if there are no pending
events for the process.

> What is really interesting is that a kill -1 on the wpa_supplicant
> process determines a reconfiguration and the and the scanning process
> is started (

SIGHUP requests a new scan to be run..

> On Sat, Aug 27, 2016 at 3:34 PM, Gucea Doru <gucea.doru at> wrote:
> >  3. wpa_supplicant -dd -Dnl80211 -iwlan0 -c./ap.conf
> > ----------
> >
> >  - logcat messages:

While this log shows a case where there is nothing requesting a scan to
be run.

> > As you can notice from the logcat messages, there are no error
> > messages (E) only debug (D) messages and the scanning/association
> > process is not started.
> >
> > **Judging from the logcat messages do you have any idea where the problem is?**

What problem? This logs seems to show expected wpa_supplicant behavior..
If you want to scan for networks on Android, you'll need something to
issue the scan command. Normally, this would be the Wi-Fi framework.
Since you are running wpa_supplicant manually with custom configuration,
Wi-Fi framework may not be able to support such a case.

> > P.S.: Just for reference, I also attach the wpa_supplicant messages
> > from a successful authentication (when wpa_supplicant is used
> > automatically by the Android framework):

And this one is showing the Android framework requesting a scan and
wpa_supplicant executing it.

Jouni Malinen                                            PGP id EFC895FA

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