Android : Processing in Android mode: where is my log file?

I'm testing a Processing sketch in Android mode, code taken from a generic tutorial. I know (I guess?), that the sketch saves a log file:

import android.util.Log;

being line at the beginning of the sketch, and then some call in the middle of code like this:

Log.e("Aldrin", "Armostrong");

Do you know where the file is saved? I looked inside the sketch folder but nothing. Obviously I'm a very newby in Android. Thanks

PS: working on a Linux system (Debian 7)