nodejs/node · error

expected parameter for argument -%c\n

Error message

expected parameter for argument -%c\n

What it means

For parameterized short options (`o/q/w/C/D/S`) brotli requires the option letter to be the LAST character in a bundled short-option token so the next argv element is consumed as its parameter. The check `j + 1 != arg_len` fails when a parameter-requiring letter is followed by more letters in the same token, e.g. `-oq`. The parser will not split the remainder as an inline value.

Source

Thrown at deps/brotli/c/tools/brotli.c:438

          /* Don't parse further. */
          return COMMAND_VERSION;
        } else if (c == 'Z') {
          if (quality_set) {
            fprintf(stderr, "quality already set\n");
            return COMMAND_INVALID;
          }
          quality_set = BROTLI_TRUE;
          params->quality = 11;
          continue;
        }
        /* o/q/w/C/D/S with parameter is expected */
        if (c != 'o' && c != 'q' && c != 'w' && c != 'C' && c != 'D' &&
            c != 'S') {
          fprintf(stderr, "invalid argument -%c\n", c);
          return COMMAND_INVALID;
        }
        if (j + 1 != arg_len) {
          fprintf(stderr, "expected parameter for argument -%c\n", c);
          return COMMAND_INVALID;
        }
        i++;
        if (i == argc || !argv[i] || argv[i][0] == 0) {
          fprintf(stderr, "expected parameter for argument -%c\n", c);
          return COMMAND_INVALID;
        }
        params->not_input_indices[next_option_index++] = i;
        if (c == 'o') {
          if (output_set) {
            fprintf(stderr, "write to standard output already set (-o)\n");
            return COMMAND_INVALID;
          }
          params->output_path = argv[i];
        } else if (c == 'q') {
          if (quality_set) {
            fprintf(stderr, "quality already set\n");
            return COMMAND_INVALID;

View on GitHub (pinned to 1b2de5e052)

Solutions

1. Move the parameterized option to the end of the bundle so its argument is the next token: `brotli -do out file`.
2. Better: separate it entirely, `brotli -d -o out file`.
3. Never put a letter after `-o`, `-q`, `-w`, `-C`, `-D`, or `-S` inside one token.

Example fix

# before
brotli -doq out in.br
# after
brotli -d -o out in.br

# bash: ensure parameterized short opts (o q w C D S) are terminal in any bundle
for a in "$@"; do
  case "$a" in
    -?*) 
      [ "${a:0:1}" = - ] && [ "${a:1:1}" != - ] || continue
      b=${a#-}
      case "$b" in
        *o*|*q*|*w*|*C*|*D*|*S*)
          last=${b: -1}
          case "$last" in o|q|w|C|D|S) ;; *) echo "param option not terminal in $a" >&2; exit 2;; esac
          ;;
      esac
      ;;
  esac
done
brotli "$@"

# bash
if ! brotli "$@"; then rc=$?; echo "brotli exit $rc; check bundling" >&2; exit "$rc"; fi

When it happens

Trigger: Bundling a parameterized option before other letters: `brotli -doq out file`, `brotli -qf 11`.

Common situations: Habit from tools that allow `-oVALUE` inline; refactoring flag order in a generated command line.

Related errors

• too many options passed
• quality already set
• write to standard output already set
• command already set when parsing -d
• force output overwrite already set\n

AI-assisted analysis of nodejs/node@1b2de5e052 (2026-08-13). Data as JSON: /api/errors/6c34d32d7d66400e. Report an issue: GitHub.