kovidgoyal/kitty · error

failed to read from file: %#v with error: %w

Error message

failed to read from file: %#v with error: %w

What it means

For --password file:PATH, the kitten reads the file with os.ReadFile; any failure (missing file, permissions, directory) is wrapped together with the path and the underlying OS error.

Source

Thrown at kittens/clipboard/main.go:59

				if f := os.NewFile(uintptr(fd), "password-fd"); f == nil {
					return 1, fmt.Errorf("invalid file descriptor: %d", fd)
				} else {
					data, err := io.ReadAll(f)
					f.Close()
					if err != nil {
						return 1, fmt.Errorf("failed to read from file descriptor: %d with error: %w", fd, err)
					}
					opts.Password = strings.TrimRightFunc(string(data), unicode.IsSpace)
				}

			} else {
				return 1, fmt.Errorf("not a valid file descriptor number: %#v", val)
			}
		case "file":
			if data, err := os.ReadFile(val); err == nil {
				opts.Password = strings.TrimRightFunc(string(data), unicode.IsSpace)
			} else {
				return 1, fmt.Errorf("failed to read from file: %#v with error: %w", val, err)
			}
		}
	}
	if len(args) > 0 {
		return 0, run_mime_loop(opts, args)
	}
	if opts.Password != "" || opts.HumanName != "" {
		return 1, fmt.Errorf("cannot use --human-name or --password in filter mode")
	}
	return 0, run_plain_text_loop(opts)
}

func EntryPoint(parent *cli.Command) {
	create_cmd(parent, clipboard_main)
}

View on GitHub (pinned to 6d5d0c4406)

Solutions

1. Confirm the file exists and is readable by the kitten process: `test -r /path/pw && echo ok`
2. Fix permissions: `chmod 600 /path/pw` and correct ownership
3. Use an absolute path; if the file is generated at runtime, ensure it is written before the kitten starts
4. Check the wrapped %w error for the real cause (ENOENT vs EACCES)

Example fix

# before
kitten clipboard get --human-name me --password file:/run/secrets/clip-pw  # not mounted
# after
# provision the secret first, then:
kitten clipboard get --human-name me --password file:/run/secrets/clip-pw

PWFILE=${PW#file:}
[ -f "$PWFILE" ] && [ -r "$PWFILE" ] || { echo "password file missing/unreadable"; exit 2; }

When it happens

Trigger: `--password file:/nonexistent/path`, an unreadable file (mode 600 owned by another user), or a path that is a directory; SELinux/AppArmor denials also land here.

Common situations: Deployments where the password file is provisioned by a secret manager that failed to mount; wrong path relative to the kitten's working directory; restrictive permissions in containers or hardened systems.

Related errors

• EPERM
• This kitten should be run as: kitten quick-access-terminal
• Incorrect owner on pwfile: uid={shm.stats.st_uid} gid={shm.s
• Too much piped data
• failed to read the directory %s with error: %w

AI-assisted analysis of kovidgoyal/kitty@6d5d0c4406 (2026-08-27). Data as JSON: /api/errors/854f17cb25745710. Report an issue: GitHub.