Build by invoking the <code>build.sh</code> script in the top-level directory. Depending on your machine this step can take anywhere from 30 minutes to several hours
<pre>./build.sh</pre>
=== Running the emulator ===
If you've built the emulator yourself you can launch it from the root *B2G* folder. First source the setup for your build, you will have to execute this step only once before launching the emulator
<pre>
source setup.sh
</pre>
Once the environment is primed launch the emulator with the following command
<pre>
emulator -writable-system -selinux permissive
</pre>