File operations for log files and session tracking previously used low-level POSIX flags including O_NOFOLLOW, which prevents opening files through symbolic links. This has been replaced with standard file mode strings ("a" for append, "w" for write). Users whose ~/.claude directory or log paths involve symbolic links (e.g., pointing to a different disk or partition) should experience fewer file operation errors.
Evidence
Removal of O_NOFOLLOW flag usage — previously set via R46.O_NOFOLLOW ?? 0 in the old version; zero occurrences remain in v2.1.55. Affects the log writer class (search for "local_bash") and session file creation.
Strings lifted out of the shipped bundle, so the claim above can be checked against them.