runtime: explain why we may access the card object directly

When we are in the constructor of RuntimeState, we may/must access the
card object directly. Let's explain why, since it may not be immediately
obvious.

Change-Id: I01f74d5f021d46679d1c9fa83fb8753382b0f88f
Related: OS#5418
---
M pySim/runtime.py
1 file changed, 20 insertions(+), 0 deletions(-)

diff --git a/pySim/runtime.py b/pySim/runtime.py
index 2447222..670babc 100644
--- a/pySim/runtime.py
+++ b/pySim/runtime.py
@@ -110,6 +110,12 @@
         # probe for those applications
         for f in sorted(set(apps_profile) - set(apps_taken), key=str):
             try:
+                # we can not use the lchan provided methods select, or select_file
+                # since those method work on an already finished file model. At
+                # this point we are still in the initialization process, so it is
+                # no problem when we access the card object directly without caring
+                # about updating other states. For normal selects at runtime, the
+                # caller must use the lchan provided methods select or select_file!
                 data, sw = self.card.select_adf_by_aid(f.aid)
                 self.selected_adf = f
                 if sw == "9000":

