{"record":{"id":"fadf0aa2bac846b6","repo":"Aider-AI/aider","slug":"error-reading-file-rel-path-e","errorCode":null,"errorMessage":"Error reading file {rel_path}: {e}","messagePattern":"Error reading file (.+?): (.+?)","errorType":"exception","errorClass":"DiffError","httpStatus":null,"severity":"error","filePath":"aider/coders/patch_coder.py","lineNumber":272,"sourceCode":"            start_index = 1  # Skip \"*** Begin Patch\"\n\n        # Identify files needed for context lookups during parsing\n        needed_paths = identify_files_needed(content)\n        current_files: Dict[str, str] = {}\n        for rel_path in needed_paths:\n            abs_path = self.abs_root_path(rel_path)\n            try:\n                # Use io.read_text to handle potential errors/encodings\n                file_content = self.io.read_text(abs_path)\n                if file_content is None:\n                    raise DiffError(\n                        f\"File referenced in patch not found or could not be read: {rel_path}\"\n                    )\n                current_files[rel_path] = file_content\n            except FileNotFoundError:\n                raise DiffError(f\"File referenced in patch not found: {rel_path}\")\n            except IOError as e:\n                raise DiffError(f\"Error reading file {rel_path}: {e}\")\n\n        try:\n            # Parse the patch text using adapted logic\n            patch_obj = self._parse_patch_text(lines, start_index, current_files)\n            # Convert Patch object actions dict to a list of tuples (path, action)\n            # for compatibility with the base Coder's prepare_to_edit method.\n            results = []\n            for path, action in patch_obj.actions.items():\n                results.append((path, action))\n            return results\n        except DiffError as e:\n            # Raise as ValueError for consistency with other coders' error handling\n            raise ValueError(f\"Error parsing patch content: {e}\")\n        except Exception as e:\n            # Catch unexpected errors during parsing\n            raise ValueError(f\"Unexpected error parsing patch: {e}\")\n\n    def _parse_patch_text(","sourceCodeStart":254,"sourceCodeEnd":290,"githubUrl":"https://github.com/Aider-AI/aider/blob/5dc9490bb35f9729ef2c95d00a19ccd30c26339c/aider/coders/patch_coder.py#L254-L290","documentation":"The IOError branch of PatchCoder's preload loop: reading the target file raised an IOError (other than FileNotFoundError) — permission denied, I/O error, or similar OS-level read failure. The original exception text is embedded in the DiffError message.","triggerScenarios":"io.read_text raises PermissionError/OSError (subclass of IOError) while preloading an '*** Update File:' path — unreadable permissions, file locked by another process, or a transient filesystem error (NFS/network mount).","commonSituations":"Files owned by another user or mode 000; editors/IDEs holding exclusive locks; flaky network mounts; containers running as a different UID than the file owner.","solutions":["Check the embedded exception text ({e}) — it names the exact OS error (errno).","Fix permissions/ownership: chmod/chown the file so the aider process can read it.","Retry after releasing locks or remounting a stalled network filesystem.","Run aider from a context with appropriate read access (correct user, container volume permissions)."],"exampleFix":"# shell fix for the reported path\nchmod u+r src/locked_file.py\n# or run aider as the file owner instead of another UID","handlingStrategy":"try-catch","validationCode":"import os\n\ndef readable(rel_paths, root):\n    problems = []\n    for rel in rel_paths:\n        p = os.path.join(root, rel)\n        if os.path.exists(p) and not os.access(p, os.R_OK):\n            problems.append(p)\n    return problems  # chmod/chown these before applying the patch","typeGuard":null,"tryCatchPattern":"try:\n    coder.get_edits(patch_text)\nexcept ValueError as e:\n    msg = str(e)\n    if msg.startswith(\"Error reading file\"):\n        fix_permissions_and_retry(msg)  # inspect embedded OS error, chmod, retry once\n    else:\n        raise","preventionTips":["Run aider with a user that has read access to the repo's files (matters in containers and shared checkouts).","Check for processes holding exclusive locks on target files before sessions.","Treat embedded IOError text as authoritative — it carries the errno."],"tags":["aider","patch-format","filesystem","permissions","io"],"backgroundTag":null,"analyzedSha":"5dc9490bb35f9729ef2c95d00a19ccd30c26339c","analyzedAt":"2026-08-15T05:40:10.498Z","schemaVersion":2},"datasetVersion":"2026-08-15T22:17:37.221Z"}