MuntashirAkon/AppManager · error

Error! debug must be either 0 or 1.\n

Error message

Error! debug must be either 0 or 1.\n

What it means

Validation guard in main(): the 8th command-line argument (debug flag) passed to this native server launcher is neither "0" nor "1". The C entry point refuses to proceed so downstream app_process calls never run with an ambiguous debug setting; the faulting input is argv[7].

Source

Thrown at app/src/main/cpp/run_server.c:98

    const char *port = argv[1];
    const char *token = argv[2];
    const char *am_jar_name = argv[3];
    const char *main_jar_name = argv[4];
    const char *app_id = argv[5];
    const char *user_id = argv[6];
    const char *debug = argv[7];
    const char *bgrun = "1";

    // Validate Paths
    if (!is_safe_string(am_jar_name) || !is_safe_string(main_jar_name) || !is_safe_string(app_id) ||
        !is_safe_string(user_id)) {
        fprintf(stderr, "Error! Invalid characters in arguments.\n");
        return 1;
    }

    // Validate debug and bgrun
    if ((strcmp(debug, "0") != 0 && strcmp(debug, "1") != 0)) {
        fprintf(stderr, "Error! debug must be either 0 or 1.\n");
        return 1;
    }

    // /data/local/tmp/am.jar
    char exec_jar_path[512];
    if (snprintf(exec_jar_path, sizeof(exec_jar_path), "%s/%s", TMP_PATH, am_jar_name) >=
        sizeof(exec_jar_path)) {
        fprintf(stderr, "Error! Buffer overflow on exec_jar_path.\n");
        return 1;
    }

    // /data/local/tmp/main.jar
    char main_jar_path[512];
    if (snprintf(main_jar_path, sizeof(main_jar_path), "%s/%s", TMP_PATH, main_jar_name) >=
        sizeof(main_jar_path)) {
        fprintf(stderr, "Error! Buffer overflow on main_jar_path.\n");
        return 1;
    }

View on GitHub (pinned to 0152f468fc)

Solutions

1. Pass debug strictly as "0" or "1" from the launcher
2. Convert booleans on the caller side with (debug ? "1" : "0")
3. If arguments were shifted, fix the argument order/count first (see the argc<8 usage error)

Example fix

// before
... + " " + debugFlag; // debugFlag = true
// after
... + " " + (debugFlag ? "1" : "0");

if (!("0".equals(debug) || "1".equals(debug)))
    throw new IllegalArgumentException("debug must be 0 or 1");

When it happens

Trigger: argv[7] != "0" and != "1" — e.g. caller passed "true"/"false", "debug", "01", or an empty string.

Common situations: Caller formats a boolean as true/false instead of 1/0; string concatenation introduces a space; an extra/missing earlier argument shifts positions so argv[7] holds the wrong value.

Understand the failure class

Background: "unknown output mode", "invalid value for flag", "expects true/false": fixing invalid flag value errors in CLI tools — this error's family across 24 libraries.

Related errors

• USAGE: %s <port> <token> <am_jar_name> <main_jar_name> <app_
• Error! Invalid characters in arguments.\n
• Unknown density {densityName}
• Package name is missing.
• No splits selected.

AI-assisted analysis of MuntashirAkon/AppManager@0152f468fc (2026-09-12). Data as JSON: /api/errors/260b29ec97c531cf. Report an issue: GitHub.