{"record":{"id":"08fe48123b354204","repo":"charmbracelet/glow","slug":"unable-to-read-from-reader-w","errorCode":null,"errorMessage":"unable to read from reader: %w","messagePattern":"unable to read from reader: %w","errorType":"exception","errorClass":null,"httpStatus":null,"severity":"error","filePath":"main.go","lineNumber":277,"sourceCode":"\t}\n\n\treturn nil\n}\n\nfunc executeArg(cmd *cobra.Command, arg string, w io.Writer) error {\n\t// create an io.Reader from the markdown source in cli-args\n\tsrc, err := sourceFromArg(arg)\n\tif err != nil {\n\t\treturn err\n\t}\n\tdefer src.reader.Close() //nolint:errcheck\n\treturn executeCLI(cmd, src, w)\n}\n\nfunc executeCLI(cmd *cobra.Command, src *source, w io.Writer) error {\n\tb, err := io.ReadAll(src.reader)\n\tif err != nil {\n\t\treturn fmt.Errorf(\"unable to read from reader: %w\", err)\n\t}\n\n\tb = utils.RemoveFrontmatter(b)\n\n\t// render\n\tvar baseURL string\n\tu, err := url.ParseRequestURI(src.URL)\n\tif err == nil {\n\t\tu.Path = filepath.Dir(u.Path)\n\t\tbaseURL = u.String() + \"/\"\n\t}\n\n\tisCode := !utils.IsMarkdownFile(src.URL)\n\n\t// initialize glamour\n\tr, err := glamour.NewTermRenderer(\n\t\tutils.GlamourStyle(style, isCode),\n\t\tglamour.WithWordWrap(int(width)), //nolint:gosec","sourceCodeStart":259,"sourceCodeEnd":295,"githubUrl":"https://github.com/charmbracelet/glow/blob/e3970c813d93da1ea84edfca90c289d9afb82242/main.go#L259-L295","documentation":"executeCLI reads the entire source (URL response body, opened file, or stdin) into memory with io.ReadAll(src.reader). This error means the read itself failed mid-stream: a connection reset while downloading remote content, a filesystem I/O error while reading a local file, or a revoked/truncated source. It is distinct from open errors - the source was obtained successfully, then reading it failed.","triggerScenarios":"Remote server drops the connection mid-body; a local file sits on failing storage (EIO); the file is truncated or removed between open and read; reading from a pipe fd returns an error rather than EOF.","commonSituations":"Unstable networks fetching large READMEs, removable media removed mid-run, NFS/filesystem faults, huge files exceeding available memory.","solutions":["Retry the fetch - mid-body resets are usually transient","Verify the source directly: curl the URL, or cat the local file to completion","For local files on odd storage, check dmesg / mount health if reads keep failing","For very large documents, render a smaller file to rule out memory exhaustion"],"exampleFix":null,"handlingStrategy":"try-catch","validationCode":null,"typeGuard":"func isNetReadErr(err error) bool {\n\tvar opErr *net.OpError\n\treturn errors.As(err, &opErr)\n}","tryCatchPattern":"b, err := io.ReadAll(src.reader)\nif err != nil {\n\tif isNetReadErr(err) {\n\t\t// transient reset mid-body: re-open the source and read again\n\t} else {\n\t\treturn fmt.Errorf(\"unable to read from reader: %w\", err)\n\t}\n}","preventionTips":["Read remote documents fully into memory with retry-on-network-error logic","Use an http.Client with Timeout so stalled bodies fail promptly","Pre-validate local files on healthy storage before rendering"],"tags":["io","network","reader"],"backgroundTag":null,"analyzedSha":"e3970c813d93da1ea84edfca90c289d9afb82242","analyzedAt":"2026-08-15T22:50:54.304Z","schemaVersion":2},"datasetVersion":"2026-08-16T03:17:38.424Z"}