{"record":{"id":"6f23c21bdf0950ea","repo":"lionsoul2014/ip2region","slug":"file-stat-w","errorCode":null,"errorMessage":"file stat: %w","messagePattern":"file stat: %w","errorType":"exception","errorClass":null,"httpStatus":null,"severity":"error","filePath":"binding/golang/xdb/util.go","lineNumber":165,"sourceCode":"\t\treturn fmt.Errorf(\"loading header: %w\", err)\n\t}\n\n\t// get the runtime ptr bytes\n\truntimePtrBytes := 0\n\tswitch header.Version {\n\tcase Structure20:\n\t\truntimePtrBytes = 4\n\tcase Structure30:\n\t\truntimePtrBytes = header.RuntimePtrBytes\n\tdefault:\n\t\treturn fmt.Errorf(\"invalid version: %d\", header.Version)\n\t}\n\n\t// 1, confirm the xdb file size.\n\t// to sure that the MaxFilePointer does no overflow\n\tstat, err := handle.Stat()\n\tif err != nil {\n\t\treturn fmt.Errorf(\"file stat: %w\", err)\n\t}\n\n\tmaxFilePtr := (int64(1) << (runtimePtrBytes * 8)) - 1\n\tif stat.Size() > maxFilePtr {\n\t\treturn fmt.Errorf(\"xdb file exceeds the maximum supported bytes: %d\", maxFilePtr)\n\t}\n\n\treturn nil\n}\n\n// VerifyFromFile check Verify for details\nfunc VerifyFromFile(dbFile string) error {\n\thandle, err := os.OpenFile(dbFile, os.O_RDONLY, 0600)\n\tif err != nil {\n\t\treturn fmt.Errorf(\"open xdb file `%s`: %w\", dbFile, err)\n\t}\n\tdefer handle.Close()\n","sourceCodeStart":147,"sourceCodeEnd":183,"githubUrl":"https://github.com/lionsoul2014/ip2region/blob/c1a1fc7d5941760db3f8431dc05c48cf7f0e30a1/binding/golang/xdb/util.go#L147-L183","documentation":"After determining runtime pointer size (4 bytes for v2, header.RuntimePtrBytes for v3), Verify stats the xdb file and wraps any Stat failure as \"file stat\". Stat errors usually mean the file handle is bad or the file vanished mid-check.","triggerScenarios":"Calling Verify/VerifyFromFile on a file deleted or renamed after opening; permission errors on the path (e.g. traversing a non-searchable directory); passing a handle to a special file that cannot be stat'ed.","commonSituations":"Hot-reloading xdb files where the replacement removes the old inode while the check runs; containers with read-only or masked mounts; symlink targets missing.","solutions":["Verify the file path resolves to an existing, readable regular file before opening","Re-open the file if it may have been replaced (path-based reopen rather than stale handle)","Check mount/permissions in containerized environments","Run Verify again after fixing the environment — this is an environmental, not format, error"],"exampleFix":"// before\nf, _ := os.OpenFile(dbFile, os.O_RDONLY, 0600)\nos.Remove(dbFile) // file gone\nerr := xdb.Verify(f) // file stat: ...\n// after\nif _, err := os.Stat(dbFile); err != nil { log.Fatalf(\"xdb missing: %v\", err) }\nf, _ := os.OpenFile(dbFile, os.O_RDONLY, 0600)\nerr = xdb.Verify(f)","handlingStrategy":"retry","validationCode":"info, err := os.Stat(dbPath)\nif err != nil { return fmt.Errorf(\"xdb stat before verify: %w\", err) }\nif !info.Mode().IsRegular() { return fmt.Errorf(\"%s is not a regular file\", dbPath) }","typeGuard":null,"tryCatchPattern":"var err error\nfor i := 0; i < 3; i++ {\n    f, e := os.OpenFile(dbPath, os.O_RDONLY, 0600)\n    if e != nil { err = e; continue }\n    err = xdb.Verify(f)\n    f.Close()\n    if err == nil || !strings.Contains(err.Error(), \"file stat\") { break }\n    time.Sleep(100 * time.Millisecond) // file may be mid-replacement\n}","preventionTips":["Replace xdb files atomically (write temp, rename) so handles never go stale","Check os.Stat success before opening the handle","Avoid deleting files behind open handles during hot reloads","Check mount/read-only/permission issues in containers"],"tags":["go","filesystem","oserror"],"backgroundTag":"file-stat-failed","analyzedSha":"c1a1fc7d5941760db3f8431dc05c48cf7f0e30a1","analyzedAt":"2026-09-02T16:58:39.988Z","contentChangedAt":null,"schemaVersion":2},"datasetVersion":"2026-09-09T21:17:11.164Z"}