cmake: Update Python install path documentation

Python install paths are notoriusly difficult to determine. This commit is an effort to provide more info on the subject. Signed-off-by: Johannes Demel <[email protected]>
gnuradio · Jul 5, 2022 · 75a98d5 · 75a98d5
1 parent 32709a6
commit 75a98d5
Showing 1 changed file with 11 additions and 5 deletions.
diff --git a/cmake/Modules/VolkPython.cmake b/cmake/Modules/VolkPython.cmake
@@ -114,17 +114,23 @@ import sysconfig
 import site
 
 install_dir = None
+# The next line passes a CMake variable into our script.
 prefix = '${CMAKE_INSTALL_PREFIX}'
 
-#use `site` when the prefix is already recognized
+# We use `site` to identify if our chosen prefix is a default one.
+# https://docs.python.org/3/library/site.html
 try:
-  paths = [p for p in site.getsitepackages() if p.startswith(prefix)]
-  if len(paths) == 1: install_dir = paths[0]
+    # https://docs.python.org/3/library/site.html#site.getsitepackages
+    paths = [p for p in site.getsitepackages() if p.startswith(prefix)]
+    if len(paths) == 1: install_dir = paths[0]
 except AttributeError: pass
 
+# If we found a default install path, `install_dir` is set.
 if not install_dir:
-    # find where to install the python module
-    # for Python 3.11+, we could use the 'venv' scheme for all platforms
+    # We use a custom install prefix!
+    # Determine the correct install path in that prefix on the current platform.
+    # For Python 3.11+, we could use the 'venv' scheme for all platforms
+    # https://docs.python.org/3.11/library/sysconfig.html#installation-paths
     if os.name == 'nt':
         scheme = 'nt'
     else: