nodejs/node · error

%s: error in command line argument "%s"\n

Error message

%s: error in command line argument "%s"\n

What it means

derb (the resource-bundle disassembler, sibling of genrb) parses its options with u_parseArgs. A negative return means a bad token; derb prints pname (program name) and the offending argv[-argc]. The subsequent block may also print a full usage banner depending on flags.

Source

Thrown at deps/icu-small/source/tools/genrb/derb.cpp:106

    /* Get the name of tool. */
    pname = uprv_strrchr(*argv, U_FILE_SEP_CHAR);
#if U_FILE_SEP_CHAR != U_FILE_ALT_SEP_CHAR
    if (!pname) {
        pname = uprv_strrchr(*argv, U_FILE_ALT_SEP_CHAR);
    }
#endif
    if (!pname) {
        pname = *argv;
    } else {
        ++pname;
    }

    /* error handling, printing usage message */
    argc=u_parseArgs(argc, argv, UPRV_LENGTHOF(options), options);

    /* error handling, printing usage message */
    if(argc<0) {
        fprintf(stderr,
            "%s: error in command line argument \"%s\"\n", pname,
            argv[-argc]);
    }
    if(argc<0 || options[0].doesOccur || options[1].doesOccur) {
        fprintf(argc < 0 ? stderr : stdout,
            "%csage: %s [ -h, -?, --help ] [ -V, --version ]\n"
            " [ -v, --verbose ] [ -e, --encoding encoding ] [ --bom ]\n"
            " [ -t, --truncate [ size ] ]\n"
            " [ -s, --sourcedir source ] [ -d, --destdir destination ]\n"
            " [ -i, --icudatadir directory ] [ -c, --to-stdout ]\n"
            " [ -A, --suppressAliases]\n"
            " bundle ...\n", argc < 0 ? 'u' : 'U',
            pname);
        return argc<0 ? U_ILLEGAL_ARGUMENT_ERROR : U_ZERO_ERROR;
    }

    if(options[10].doesOccur) {
        fprintf(stderr,

View on GitHub (pinned to 1b2de5e052)

Solutions

1. Run `derb -h` to list supported options and remove the offending token shown in the message.
2. Confirm each value-taking flag (-e, -t, -s, -d, -i) is followed by its argument.
3. Check the derb invocation in your script against the documented option set.

// derb supported flags
VALID_DERB = {'-h','-?','--help','-V','--version','-v','--verbose','-e','--encoding','--bom','-t','--truncate','-s','--sourcedir','-d','--destdir','-i','--icudatadir','-c','--to-stdout','-A','--suppressAliases'}
bad = [a for a in argv[1:] if a.startswith('-') and a.split('=')[0] not in VALID_DERB]
if bad: raise SystemExit(f'unknown derb option(s): {bad}')

When it happens

Trigger: Passing an unknown option, an option requiring a value without one (e.g. -e with no encoding), or otherwise malformed arguments to derb. pname is derived from argv[0] (stripped to the basename).

Common situations: Running derb by hand with a typo'd flag; using a flag that belongs to genrb, not derb; a wrapper script that injects an extra option derb does not understand.

Related errors

• %s: Error: don't specify an encoding (-e) when writing to st
• %s: error in command line argument "%s"\n
• error in command line argument "%s"\n
• error in command line argument "%s"\n
• %s: cannot combine --writePoolBundle and --usePoolBundle\n

AI-assisted analysis of nodejs/node@1b2de5e052 (2026-08-13). Data as JSON: /api/errors/f269194a62c012d2. Report an issue: GitHub.