在这个信息爆炸的时代，短信虽然不再是日常沟通的主力军，但在某些场景下，如国际漫游、没有网络覆盖的偏远地区，发送长篇内容依然是人们的首选。那么，如何轻松发送超长短信呢？这就需要了解短信PDU（Protocol Data Unit）格式及其相关技巧。下面，我就来为大家详细解析。
一、短信PDU格式详解
短信PDU是短信发送和接收过程中的一个关键概念，它代表了短信在手机网络中的传输格式。了解PDU格式，有助于我们更好地发送和接收短信。
1. PDU结构
一个完整的PDU由以下几个部分组成：
- 协议类型：指示短信类型，如文本消息、图片消息等。
- 服务中心地址：接收短信的服务中心地址。
- 短信长度：短信内容的字节数。
- 用户数据：短信内容。
2. PDU格式示例
以下是一个文本消息的PDU格式示例：
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