<screen xmlns="http://www.scons.org/dbxsd/v1.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.scons.org/dbxsd/v1.0 http://www.scons.org/dbxsd/v1.0/scons.xsd">% <userinput>scons -Q CONFIG=/does/not/exist foo.o</userinput>

scons: *** Path for variable 'CONFIG' does not exist: /does/not/exist
File "/home/my/project/SConstruct", line 7, in &lt;module&gt;
</screen>
