}
    }

    public void test_execute_2instance() throws Exception {
        final CrawlerWebServer server1 = new CrawlerWebServer(7070);
        server1.start();
        final CrawlerWebServer server2 = new CrawlerWebServer(7071);
        server2.start();

        final String url1 = "http://localhost:7070/";
        final String url2 = "http://localhost:7071/";
        try {
            final int maxCount = 10;

        assertSame(buffer, derivedBuffer.buf);
        assertEquals(0, derivedBuffer.start); // Derived buffer starts from the original buffer's start
        assertEquals(10, derivedBuffer.index);
        assertSame(ndrBuffer.deferred, derivedBuffer.deferred); // Deferred should be the same as original

        // Ensure changes to derived buffer don't affect original's index/start
        derivedBuffer.advance(5);
        assertEquals(15, derivedBuffer.index);

        if (oldProcess != null) {
            destroyProcess(sessionId, oldProcess);
        }

        // Start the new process and add it to the map
        try {
            final JobProcess jobProcess = new JobProcess(pb.start(), bufferSize, outputCallback);
            runningProcessMap.put(sessionId, jobProcess);
            return jobProcess;
        } catch (final IOException e) {

    require(length < bytesOut.size - lastFrame.start)

    // Move everything from bytesOut into a new buffer.
    val fullBuffer = Buffer()
    bytesOut.read(fullBuffer, bytesOut.size)

    // Copy back all but what we're truncating.
    fullBuffer.read(bytesOut, lastFrame.start + length)
    outFrames.add(OutFrame(lastFrame.sequence, lastFrame.start, true))
    return writer
  }

## Lifespan { #lifespan }

You can define this *startup* and *shutdown* logic using the `lifespan` parameter of the `FastAPI` app, and a "context manager" (I'll show you what that is in a second).

Let's start with an example and then see it in detail.

        info.bytesPerSect = readInt2(buffer, bufferIndex);
        bufferIndex += 4;

        this.info = info;

        return bufferIndex - start;
    }

    int readSmbQueryFSSizeInfoWireFormat(final byte[] buffer, int bufferIndex) {
        final int start = bufferIndex;

        final SmbInfoAllocation info = new SmbInfoAllocation();

        info.alloc = readInt8(buffer, bufferIndex);

        final int start = dstIndex;
        dstIndex += calledName.writeWireFormat(dst, dstIndex);
        dstIndex += callingName.writeWireFormat(dst, dstIndex);
        return dstIndex - start;
    }

    @Override
    int readTrailerWireFormat(final InputStream in, final byte[] buffer, int bufferIndex) throws IOException {
        final int start = bufferIndex;

    }

    @Override
    public int encode(byte[] dst, int dstIndex) {
        int start = dstIndex;

        // Write context header
        SMBUtil.writeInt4(0, dst, dstIndex); // Next (offset to next context, 0 for last)
        dstIndex += 4;

        SMBUtil.writeInt2(16, dst, dstIndex); // NameOffset (from start of context)
        dstIndex += 2;

        SMBUtil.writeInt2(4, dst, dstIndex); // NameLength

     */
    private void buildHeader(byte[] buf, int start, int status, int command, long sessionId) {
        System.arraycopy(SMBUtil.SMB2_HEADER, 0, buf, start, SMBUtil.SMB2_HEADER.length);
        // Status at +8
        SMBUtil.writeInt4(status, buf, start + 8);
        // Command at +12
        SMBUtil.writeInt2(command, buf, start + 12);
        // Flags at +16: server-to-redirector

        dstIndex += 2;
        SMBUtil.writeInt4(this.offset >> 32, dst, dstIndex);
        dstIndex += 4;

        return dstIndex - start;
    }

    @Override
    protected int writeBytesWireFormat(final byte[] dst, int dstIndex) {
        final int start = dstIndex;

        while (this.pad-- > 0) {
            dst[dstIndex] = (byte) 0xEE;
            dstIndex++;
        }