INFO: Winsock Ignores ICMP Port Unreachable Control Messages

• Microsoft Windows NT, versions 3.1, 3.5, 3.51, 4.0
• Microsoft Windows versions 95, 98, 98 Second Edition

SUMMARY

ICMP Port Unreachable control messages are ignored by the Winsock layer on versions of Windows as specified applies to section. If Winsock UDP application is sending datagram to a host application that has already gone, the host replies with ICMP Port Unreachable control message. If the Winsock application is then blocking on receiving datagram from the peer, it will not unblock on receiving the ICMP Port Unreachable control message. If the application needs to detect the existence of the UDP peer under such scenarios, it may use nonblocking socket or overlapped socket with timeout and retries.

MORE INFORMATION

On Windows 2000, a feature is added to unblock Winsock application and returning 10054 (WSA_ECONNRESET) through WSAGetLastError if ICMP Host Unreachable control message is received for a bound socket.

Additional query words:

Keywords : kbnetwork kbAPI kbNTOS310 kbNTOS350 kbNTOS351 kbNTOS400 kbSDKPlatform kbWinOS95 kbWinOS98 kbWinsock kbDSupport kbGrpNet
Version : WINDOWS:95,98,98 Second Edition; winnt:3.1,3.5,3.51,4.0
Platform : WINDOWS winnt
Issue type : kbinfo