SMBUtil.writeInt4(this.originalMessageSize, dst, dstIndex);
        dstIndex += 4;

        // Reserved (2 bytes)
        SMBUtil.writeInt2(0, dst, dstIndex);
        dstIndex += 2;

        // Flags (2 bytes)
        SMBUtil.writeInt2(this.flags, dst, dstIndex);
        dstIndex += 2;

        // Session ID (8 bytes)
        SMBUtil.writeInt8(this.sessionId, dst, dstIndex);

        byte[] buffer = new byte[32];
        // Mock data for FsFullSizeInformation
        writeInt8(3000, buffer, 0); // total allocation units
        writeInt8(1500, buffer, 8); // caller available allocation units
        writeInt8(1500, buffer, 16); // actual free units (skipped)
        writeInt4(4, buffer, 24); // sectors per allocation unit
        writeInt4(8192, buffer, 28); // bytes per sector

            SMBUtil.writeInt2(80, dst, dstIndex); // ReadChannelInfoOffset (after header)
            SMBUtil.writeInt2(16, dst, dstIndex + 2); // ReadChannelInfoLength
            dstIndex += 4;
        } else {
            SMBUtil.writeInt2(0, dst, dstIndex);
            SMBUtil.writeInt2(0, dst, dstIndex + 2);
            dstIndex += 4;
        }

        // Status at +8
        SMBUtil.writeInt4(status, buf, start + 8);
        // Command at +12
        SMBUtil.writeInt2(command, buf, start + 12);
        // Flags at +16: server-to-redirector
        SMBUtil.writeInt4(0x00000001, buf, start + 16);
        // SessionId at +40 (sync header)
        SMBUtil.writeInt8(sessionId, buf, start + 40);
    }

    /**

        int start = dstIndex;

        // StructureSize (2 bytes) - must be 36
        SMBUtil.writeInt2(STRUCTURE_SIZE, dst, dstIndex);
        dstIndex += 2;

        // Reserved (2 bytes)
        SMBUtil.writeInt2(0, dst, dstIndex);
        dstIndex += 2;

        // Flags (4 bytes)
        SMBUtil.writeInt4(flags, dst, dstIndex);
        dstIndex += 4;

        // LeaseKey (16 bytes)

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

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

        SMBUtil.writeInt2(4, buffer, offset); // NameLength
        offset += 2;

        SMBUtil.writeInt2(0, buffer, offset); // Reserved
        offset += 2;

            SMBUtil.writeInt2(transformOffset, dst, dstIndex); // writeChannelInfoOffset
            SMBUtil.writeInt2(16, dst, dstIndex + 2); // writeChannelInfoLength (size of SMB2_RDMA_TRANSFORM)
        } else {
            SMBUtil.writeInt2(0, dst, dstIndex); // writeChannelInfoOffset
            SMBUtil.writeInt2(0, dst, dstIndex + 2); // writeChannelInfoLength
        }
        dstIndex += 4;

        // 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
        dstIndex += 2;

        SMBUtil.writeInt2(0, dst, dstIndex); // Reserved
        dstIndex += 2;

        // 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
        dstIndex += 2;

        SMBUtil.writeInt2(0, dst, dstIndex); // Reserved
        dstIndex += 2;

            System.arraycopy(SMBUtil.SMB2_HEADER, 0, buffer, 0, 4);
            // Set up sync message fields
            SMBUtil.writeInt4(0, buffer, 16); // flags (no async flag)
            SMBUtil.writeInt4(123, buffer, 36); // tree ID
            SMBUtil.writeInt8(456L, buffer, 40); // session ID
            return buffer;
        }

        private byte[] createValidAsyncMessage() {