diff --git a/README.adoc b/README.adoc
index 83afd05..d7db803 100644
--- a/README.adoc
+++ b/README.adoc
@@ -11305,6 +11305,18 @@ You can also choose a different configuration file explicitly with:
 ./run --config data/config2.py
 ....
 
+Almost all options names are automatically deduced from their command line `--help` name: just replace `-` with `_`.
+
+More precisely, we use the `dest=` value of Python's link:https://docs.python.org/3/library/argparse.html[argparse module].
+
+To get a list of all global options that you can use, try:
+
+....
+./getvar --type input
+....
+
+but note that this does not include script specific options.
+
 === Build the documentation
 
 You don't need to depend on GitHub:
diff --git a/common.py b/common.py
index 24cf4fa..b0aef16 100644
--- a/common.py
+++ b/common.py
@@ -786,6 +786,7 @@ Valid emulators: {}
         Time the main of the derived class.
         '''
         env = kwargs.copy()
+        self.input_args = env.copy()
         env.update(consts)
         real_all_archs= env['all_archs']
         if real_all_archs:
diff --git a/config.py b/config.py
index 9f0a606..4846754 100644
--- a/config.py
+++ b/config.py
@@ -1,3 +1,7 @@
+'''
+https://github.com/cirosantilli/linux-kernel-module-cheat#default-command-line-arguments
+'''
+
 def set_args(args, script_name):
     args['arch'] = 'aarch64'
     args['emulators'] = ['gem5']
diff --git a/getvar b/getvar
index 3f62b10..5c24380 100755
--- a/getvar
+++ b/getvar
@@ -29,6 +29,7 @@ List all available variables:
 ....
 ''',
         )
+        self.add_argument('--type', choices=['input', 'all'], default='all')
         self.add_argument('variable', nargs='?')
 
     def timed_main(self):
@@ -36,7 +37,11 @@ List all available variables:
         if variable:
             print(self.env[variable])
         else:
-            for key in self.env:
+            if self.env['type'] == 'input':
+                to_print = self.input_args
+            elif self.env['type'] == 'all':
+                to_print = self.env
+            for key in sorted(to_print):
                 print('{}={}'.format(key, self.env[key]))
 
 if __name__ == '__main__':