python · ambv · May 20, 2025 · May 20, 2025 · May 20, 2025 · May 20, 2025
diff --git a/Lib/site.py b/Lib/site.py
@@ -75,6 +75,7 @@
 import _sitebuiltins
 import io
 import stat
+import errno

 # Prefixes for site-packages; add additional prefixes like /usr/local here
 PREFIXES = [sys.prefix, sys.exec_prefix]
@@ -576,6 +577,11 @@ def write_history():
                # home directory does not exist or is not writable
                # https://bugs.python.org/issue19891
                pass
+            except OSError:
+                if errno.EROFS:
+                    pass  # gh-128066: read-only file system
+                else:
+                    raise

        atexit.register(write_history)


diff --git a/Misc/NEWS.d/next/Core_and_Builtins/2025-05-20-14-41-50.gh-issue-128066.qzzGfv.rst b/Misc/NEWS.d/next/Core_and_Builtins/2025-05-20-14-41-50.gh-issue-128066.qzzGfv.rst
@@ -0,0 +1,3 @@
+Fixes an edge case where PyREPL improperly threw an error when Python is
+invoked on a read only filesystem while trying to write history file
+entries.