MIB_TCPSTATS_LH structure (tcpmib.h)
The MIB_TCPSTATS structure contains statistics for the TCP protocol running on the local computer.
Syntax
typedef struct _MIB_TCPSTATS_LH {
union {
DWORD dwRtoAlgorithm;
TCP_RTO_ALGORITHM RtoAlgorithm;
};
DWORD dwRtoMin;
DWORD dwRtoMax;
DWORD dwMaxConn;
DWORD dwActiveOpens;
DWORD dwPassiveOpens;
DWORD dwAttemptFails;
DWORD dwEstabResets;
DWORD dwCurrEstab;
DWORD dwInSegs;
DWORD dwOutSegs;
DWORD dwRetransSegs;
DWORD dwInErrs;
DWORD dwOutRsts;
DWORD dwNumConns;
} MIB_TCPSTATS_LH, *PMIB_TCPSTATS_LH;
Members
dwRtoAlgorithm
Type: DWORD
The retransmission time-out (RTO) algorithm in use. This member can be one of the following values:
| Value | Meaning |
|---|---|
|
Other |
|
Constant Time-out |
|
MIL-STD-1778 Appendix B |
|
Van Jacobson's Algorithm |
RtoAlgorithm
dwRtoMin
Type: DWORD
The minimum RTO value in milliseconds.
dwRtoMax
Type: DWORD
The maximum RTO value in milliseconds.
dwMaxConn
Type: DWORD
The maximum number of connections. If this member is -1, the maximum number of connections is variable.
dwActiveOpens
Type: DWORD
The number of active opens. In an active open, the client is initiating a connection with the server.
dwPassiveOpens
Type: DWORD
The number of passive opens. In a passive open, the server is listening for a connection request from a client.
dwAttemptFails
Type: DWORD
The number of failed connection attempts.
dwEstabResets
Type: DWORD
The number of established connections that were reset.
dwCurrEstab
Type: DWORD
The number of currently established connections.
dwInSegs
Type: DWORD
The number of segments received.
dwOutSegs
Type: DWORD
The number of segments transmitted. This number does not include retransmitted segments.
dwRetransSegs
Type: DWORD
The number of segments retransmitted.
dwInErrs
Type: DWORD
The number of errors received.
dwOutRsts
Type: DWORD
The number of segments transmitted with the reset flag set.
dwNumConns
Type: DWORD
The number of connections that are currently present in the system. This total number includes connections in all states except listening connections.
Remarks
The GetTcpStatistics function returns a pointer to a MIB_TCPSTATS structure.
The MIB_TCPSTATS structure changed slightly on Windows Vista and later. On Windows Vista and later, the dwRtoAlgorithm member is replaced by a union that contains the following members.
In the Windows SDK, the version of the structure for use on Windows Vista and later is defined as MIB_TCPSTATS_LH. In the Windows SDK, the version of this structure to be used on earlier systems including Windows 2000 and later is defined as MIB_TCPSTATS_W2K. When compiling an application if the target platform is Windows Vista and later (NTDDI_VERSION >= NTDDI_LONGHORN, _WIN32_WINNT >= 0x0600, or WINVER >= 0x0600), the MIB_TCPSTATS_LH structure is typedefed to the MIB_TCPSTATS structure. When compiling an application if the target platform is not Windows Vista and later, the MIB_TCPSTATS_W2K structure is typedefed to the MIB_TCPSTATS structure.
On the Microsoft Windows Software Development Kit (SDK) released for Windows Vista and later, the organization of header files has changed. This structure is defined in the Tcpmib.h header file, not in the Iprtrmib.h header file. Note that the Tcpmib.h header file is automatically included in Iprtrmib.h, which is automatically included in the Iphlpapi.h header file. The Tcpmib.h and Iprtrmib.h header files should never be used directly.
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Windows 2000 Professional [desktop apps only] |
| Minimum supported server | Windows 2000 Server [desktop apps only] |
| Header | tcpmib.h (include Iphlpapi.h) |