smb.useUnicode = true;
        smb.headerStart = 1; // Make the start odd
        String testString = "Aligned Unicode";
        byte[] buffer = new byte[testString.length() * 2 + 2 + 1]; // +1 for alignment
        int len = smb.writeString(testString, buffer, 1);
        // When dstIndex=1 and headerStart=1, (1-1)%2=0, no alignment padding needed

 * such as security descriptor queries and file change notifications.
 */
public abstract class SmbComNtTransaction extends SmbComTransaction {

    // relative to headerStart
    private static final int NTT_PRIMARY_SETUP_OFFSET = 71;
    private static final int NTT_SECONDARY_PARAMETER_OFFSET = 51;

    /**
     * NT transaction function code for querying security descriptors.

    private void setHeaderStart(Smb2ChangeNotifyResponse response, int headerStart) throws Exception {
        Method method = ServerMessageBlock2.class.getDeclaredMethod("getHeaderStart");
        method.setAccessible(true);

        Field field = ServerMessageBlock2.class.getDeclaredField("headerStart");
        field.setAccessible(true);
        field.setInt(response, headerStart);
    }

    /**

        // For Unicode: 1 byte (initial null in writeBytesWireFormat)
        // + potential 1 byte alignment (in writeString) + fileName.length() * 2 + 2 bytes (terminating nulls)
        // Since headerStart is 0 and dstIndex starts at 1 (after initial null), (1-0)%2=1, so alignment byte added
        // Total: 1 + 1 + 12*2 + 2 = 28 bytes
        byte[] dst = new byte[30]; // Use extra buffer space to avoid index errors

    private static final int DEFAULT_MAX_DATA_COUNT =
            Config.getInt("jcifs.smb1.smb.client.transaction_buf_size", SmbComTransaction.TRANSACTION_BUF_SIZE) - 512;

    // relative to headerStart
    private static final int PRIMARY_SETUP_OFFSET = 61;
    private static final int SECONDARY_PARAMETER_OFFSET = 51;

    private static final int DISCONNECT_TID = 0x01;

        // Verify negotiate context offset is set
        int contextOffset = SMBUtil.readInt4(buffer, 28);
        assertTrue(contextOffset > 0);

        // Skip detailed context verification since we can't access headerStart
        // Just verify that contexts were written
        assertTrue(bytesWritten > 60); // Should be larger than basic negotiate request
    }

    @Test

        response = new Smb2QueryDirectoryResponse(mockConfig, Smb2QueryDirectoryRequest.FILE_BOTH_DIRECTORY_INFO);

        byte[] buffer = new byte[1024];
        int bufferIndex = 200;
        int headerStart = 50;

        // Set structure size to 9
        SMBUtil.writeInt2(9, buffer, bufferIndex);
        // Set buffer offset (relative to header start)
        SMBUtil.writeInt2(300, buffer, bufferIndex + 2);

            testBlock.setUseUnicode(true);
            byte[] buffer = new byte[100];
            String testString = "Test";

            // Test odd Unicode alignment - headerStart affects alignment
            int bytesWritten = testBlock.writeString(testString, buffer, 2);

            // When even alignment (offset 2), Unicode string starts immediately

        void testPad8() {
            testMessage.encode(new byte[1024], 0);
            // After header is written, padding depends on position
            int headerStart = testMessage.getHeaderStart();
            assertEquals(0, headerStart); // Should start at 0
        }
    }

    @Nested
    @DisplayName("Encode/Decode Tests")
    class EncodeDecodeTests {

        @Test