proto_logcat.java

private static String readLogcat(long startTimeMs) {
    try {
        ...
        // Start the process
        final Process process = new ProcessBuilder()
                .command("logcat", "-d", "-v threadtime,uid", "-T", timestamp)
                .start();

        // Nothing to write. Don't let the command accidentally block.
        process.getOutputStream().close();

        // Read the output
        final StringBuilder str = new StringBuilder();
        final InputStreamReader reader = new InputStreamReader(process.getInputStream());
        char[] buffer = new char[4096];
        int amt;
        while ((amt = reader.read(buffer, 0, buffer.length)) >= 0) {
            if (amt > 0) {
                str.append(buffer, 0, amt);
            }
        }

        try {
            process.waitFor();
        } catch (InterruptedException ex) {
            // We already have the text, drop the exception.
        }

        return str.toString();

    } catch (IOException ex) {
        return "Error reading logcat command:\n" + ex.toString();
    }
}