tcpinfo_t Structure

The tcpinfo_t structure is a DTrace translated version of the TCP header.

typedef struct tcpinfo {
        uint16_t tcp_sport;             /* source port */
        uint16_t tcp_dport;             /* destination port */
        uint32_t tcp_seq;               /* sequence number */
        uint32_t tcp_ack;               /* acknowledgment number */
        uint8_t tcp_offset;             /* data offset, in bytes */
        uint8_t tcp_flags;              /* flags */
        uint16_t tcp_window;            /* window size */
        uint16_t tcp_checksum;          /* checksum */
        uint16_t tcp_urgent;            /* urgent data pointer */
        tcph_t *tcp_hdr;                /* raw TCP header */
} tcpinfo_t;

Table 11-69 tcpinfo_t Members

Member	Description
tcp_sport	TCP source port.
tcp_dport	TCP destination port.
tcp_seq	TCP sequence number.
tcp_ack	TCP acknowledgment number.
tcp_offset	Payload data offset, in bytes not 32-bit words.
tcp_flags	TCP flags. See the tcp_flagstable below for available macros.
tcp_window	TCP window size, bytes.
tcp_checksum	Checksum of TCP header and payload.
tcp_urgent	TCP urgent data pointer, bytes.
tcp_hdr	Pointer to raw TCP header at time of tracing.

Table 11-70 tcp_flags Values

Value	Description
TH_FIN	No more data from sender (finish).
TH_SYN	Synchronize sequence numbers (connect).
TH_RST	Reset the connection.
TH_PUSH	TCP push function.
TH_ACK	Acknowledgment field is set.
TH_URG	Urgent pointer field is set.
TH_ECE	Explicit congestion notification echo. For more information, see RFC 3168.
TH_CWR	Congestion window reduction.

See RFC 793 for a detailed explanation of the standard TCP header fields and flags.