subdir('subdir') python3 = import('python3').find_python() fake_generator_script = ''' import os, sys assert os.path.exists(sys.argv[1]), "File %s not found" % sys.argv[1] print("This is a generated resource.") ''' # Generate file res3.txt from file res3.txt.in. This is then included # in a GResource file, driven by resources/meson.build. res3_txt = custom_target('res3.txt', input: 'res3.txt.in', output: 'res3.txt', command: [python3, '-c', fake_generator_script, '@INPUT@'], capture: true, )