wpa_supplicant logging support not working

[Stanislaw Pitucha]

I'm trying to debug an issue with my wifi connection, however the wpa_supplicant logging is not working well.

In the network interfaces, I added options:

   wpa-verbose y
   wpa-debug-level 3
   wpa-logfile /var/log/wpa_supplicant.log

This unfortunately resulted in:

1. Errors about /dev/stderr and /dev/stdout not being available
2. The file /var/log/wpa_supplicant.log is created, but empty
3. Something weird happening to wpa_supplicant options - the log now contains:

  Mar 7 14:17:03 raspberrypi wpa_supplicant[291]: Successfully initialized wpa_supplicant
  Mar 7 14:17:03 raspberrypi wpa_supplicant[291]: Could not read interface --all flags: No such device

unfortunately I couldn't track down where does the `--all` option come from.

[Stanislaw Pitucha (viraptor-gmail)]

/dev errors:

Mar 7 14:17:03 raspberrypi ifup[279]: /etc/network/if-pre-up.d/wpasupplicant: line 71: set: write error: Broken pipe
Mar 7 14:17:03 raspberrypi ifup[279]: /etc/wpa_supplicant/functions.sh: line 114: /dev/stdout: No such device or address
Mar 7 14:17:03 raspberrypi ifup[279]: /etc/wpa_supplicant/functions.sh: line 114: /dev/stdout: No such device or address

[Stanislaw Pitucha (viraptor-gmail)]

Just realised these may be separate issues. Maybe activating the logging reveals that wpa_supplicant is being called with option `--all` as the interface and that fails.