c - 我必须向服务器发送哪些参数？

Question

我无法向服务器发送有效请求。我有这个协议(protocol)描述，但我不明白我必须用 socat 将什么东西发送到服务器。

header Must always be transmitted in full, even if the command does not require any parameters.

command This is a single letter whose case is important (commands 'A' and 'a' are very different, indeed, for example). It is 8 bit in size.

param 1 This is a 16 bit numeric parameter. It is in network byte order and mostly used to specify KNX device addresses or data lengths.

我的问题来自param。我必须发送一个空值的 16 位数字参数。我该怎么做？

Answer 1

通常，“空值”仅表示您发送零。

如果服务器套接字是 sock，那么这将发送 16 位:

send (sock, "\0\0", 2, 0);