Starting from Windows 10, `IPPROTO_TCP` supported option `TCP_FASTOPEN`. Doc: https://docs.microsoft.com/en-us/windows/win32/winsock/ipproto-tcp-socket-options Macro is defined in `ws2ipdef.h` ```c++ #define TCP_FASTOPEN 15 ```
Starting from Windows 10,
IPPROTO_TCPsupported optionTCP_FASTOPEN.Doc: https://docs.microsoft.com/en-us/windows/win32/winsock/ipproto-tcp-socket-options
Macro is defined in
ws2ipdef.h