Add a bit TCPI_OPT_SYN_DATA (32) to the socket option TCP_INFO:tcpi_options. It's set if the data in SYN (sent or received) is acked by SYN-ACK. Server or client application can use this information to check Fast Open success rate.
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| @@ -130,6 +130,7 @@ enum { · 129 unmodified lines | |||
| 130 | #define TCPI_OPT_WSCALE 4 | 130 | #define TCPI_OPT_WSCALE 4 |
| 131 | #define TCPI_OPT_ECN 8 /* ECN was negociated at TCP session init */ | 131 | #define TCPI_OPT_ECN 8 /* ECN was negociated at TCP session init */ |
| 132 | #define TCPI_OPT_ECN_SEEN 16 /* we received at least one packet with ECT */ | 132 | #define TCPI_OPT_ECN_SEEN 16 /* we received at least one packet with ECT */ |
| 133 | #define TCPI_OPT_SYN_DATA 32 /* SYN-ACK acked data in SYN sent or rcvd */ | ||
| 133 | 134 | ||
| 134 | enum tcp_ca_state { | 135 | enum tcp_ca_state { |
| 135 | TCP_CA_Open = 0, | 136 | TCP_CA_Open = 0, |