Python Socket操作的异常处理范例：
http://blog.chinaunix.net/uid-270894-id-2452366.html
socket常见错误码详解：
Socket error 10048 - Address already in use (bind)
Socket error 10049 - Cannot assign requested address 无法使用该地址(bind)
Socket error 10054 - Connection reset by peer 远程主机已关闭(send，recv？？)
Socket error 10060 - Connection timed out 由于服务端长时间不接受，客户端连接超时(connect)
Socket error 10061 - Connection refused 服务端主动拒绝连接(connect)
Socket error 10065 - No route to host 无法连接主机(connect)
Socket 错误码和描述：
Socket error 0 - Directly send error
Socket error 10004 - Interrupted function call
Socket error 10013 - Permission denied
Socket error 10014 - Bad address
Socket error 10022 - Invalid argument
Socket error 10024 - Too many open files
Socket error 10035 - Resource temporarily unavailable
Socket error 10036 - Operation now in progress
Socket error 10037 - Operation already in progress
Socket error 10038 - Socket operation on non-socket
Socket error 10039 - Destination address required
Socket error 10040 - Message too long
Socket error 10041 - Protocol wrong type for socket
Socket error 10042 - Bad protocol option
Socket error 10043 - Protocol not supported
Socket error 10044 - Socket type not supported
Socket error 10045 - Operation not supported
Socket error 10046 - Protocol family not supported
Socket error 10047 - Address family not supported by protocol family
Socket error 10048 - Address already in use
Socket error 10049 - Cannot assign requested address
Socket error 10050 - Network is down
Socket error 10051 - Network is unreachable
Socket error 10052 - Network dropped connection on reset
Socket error 10053 - Software caused connection abort
Socket error 10054 - Connection reset by peer
Socket error 10055 - No buffer space available
Socket error 10056 - Socket is already connected
Socket error 10057 - Socket is not connected
Socket error 10058 - Cannot send after socket shutdown
Socket error 10060 - Connection timed out
Socket error 10061 - Connection refused
Socket error 10064 - Host is down
Socket error 10065 - No route to host
Socket error 10067 - Too many processes
Socket error 10091 - Network subsystem is unavailable
Socket error 10092 - WINSOCK.DLL version out of range
Socket error 10093 - Successful WSAStartup not yet performed
Socket error 10094 - Graceful shutdown in progress
Socket error 11001 - Host not found
Socket error 11002 - Non-authoritative host not found
Socket error 11003 - This is a non-recoverable error
Socket error 11004 - Valid name, no data record of requested type
windows命令：net helpmsg *** 可以查询错误码的更详细解释