buf.readBigInt64BE([offset])

• offset <integer> 开始读取之前要跳过的字节数。 必须满足：0 <= offset <= buf.length - 8。 默认值: 0。
• 返回: <bigint>

从指定的 offset 处的 buf 读取有符号的大端序 64 位整数。

从 Buffer 读取的整数被解释为二进制补码有符号值。

• offset <integer> Number of bytes to skip before starting to read. Must satisfy: 0 <= offset <= buf.length - 8. Default: 0.
• Returns: <bigint>

Reads a signed, big-endian 64-bit integer from buf at the specified offset.

Integers read from a Buffer are interpreted as two's complement signed values.