# SetMsgHead

### int SetMsgHead(int lMsgId, byte\[] pnHeader)

생성된 메시지 객체(`lMsgId`)에 SECS-II 표준의 10바이트 메시지 헤더 정보를 설정합니다. 이 헤더에는 Stream, Function, Device ID, Transaction ID 등 통신에 필요한 모든 주소 정보가 포함됩니다.

Parameters

| **Name** | **Type** | **Description**                             |
| -------- | -------- | ------------------------------------------- |
| lMsgId   | int      | 헤더를 설정할 대상 메시지 ID                           |
| pnHeader | byte\[]  | 10바이트 길이의 헤더 데이터 배열 (Stream, Function 등 포함) |

```csharp
void BuildS1F1Message()
{
    int lMsgId = m_gem.CreateEmptyMsg();
    if (lMsgId > 0)
    {
        // 10바이트 헤더 구성 (예: S1F1)
        // [0][1]: Device ID, [2]: Stream(1) | Wait Bit, [3]: Function(1), ...
        byte[] header = new byte[10] { 0x00, 0x00, 0x81, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01 };
        
        int result = m_gem.SetMsgHead(lMsgId, header);
        
        if (result >= 0)
        {
            // 헤더 설정 성공, 이제 Body를 구성하거나 전송
            m_gem.SendMsg(lMsgId);
        }
    }
}
```


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