tcp

问题 Problem description I'm using psycopg2 to connect to my PostgreSQL database on a remote host. I open a connection and wait for requests, then for each request I run queries on the connection and return data. But when the network connection is lost after the connection is already open the next db query hangs and I have to kill the program manually. Details: it hangs for at least 2 hours (I couldn't wait longer) the "network down" situation is actually VPN going down (db host is accesible only

问题 Problem description I'm using psycopg2 to connect to my PostgreSQL database on a remote host. I open a connection and wait for requests, then for each request I run queries on the connection and return data. But when the network connection is lost after the connection is already open the next db query hangs and I have to kill the program manually. Details: it hangs for at least 2 hours (I couldn't wait longer) the "network down" situation is actually VPN going down (db host is accesible only

问题 Problem description I'm using psycopg2 to connect to my PostgreSQL database on a remote host. I open a connection and wait for requests, then for each request I run queries on the connection and return data. But when the network connection is lost after the connection is already open the next db query hangs and I have to kill the program manually. Details: it hangs for at least 2 hours (I couldn't wait longer) the "network down" situation is actually VPN going down (db host is accesible only

问题 I need bit clarification on using multiple send/recv in socket programs. My client program looks below(Using TCP SOCK_STREAM). send(sockfd,"Messgfromlient",15,0); send(sockfd,"cli1",5,0); send(sockfd,"cli2",5,0); send(sockfd,"cli3",5,0); send(sockfd,"cli4",5,0); send(sockfd,"cli5",5,0); and the server program looks like below. recv(newsockfd,buf,20,0); printf("Buffer is %s\n",buf); when i execute the above program, the output is as below: Client Msg :Messgfromlient I believe that the buf size

问题 I need bit clarification on using multiple send/recv in socket programs. My client program looks below(Using TCP SOCK_STREAM). send(sockfd,"Messgfromlient",15,0); send(sockfd,"cli1",5,0); send(sockfd,"cli2",5,0); send(sockfd,"cli3",5,0); send(sockfd,"cli4",5,0); send(sockfd,"cli5",5,0); and the server program looks like below. recv(newsockfd,buf,20,0); printf("Buffer is %s\n",buf); when i execute the above program, the output is as below: Client Msg :Messgfromlient I believe that the buf size

问题 I did something really stupid. I was running a postgreSQL on my mac, with a few databases in it. Recently I noticed a new user called PostgreSQL was added at my login screen, and I didn't find a better idea to remove this user. Now, my pgAdminIII doesn't connect to the server anymore, giving this error when I try to connect: Server doesn't listen The server doesn't accept connections: the connection library reports could not connect to server: Connection refused Is the server running on host

问题 Linux has ioctl SIOCOUTQ described in man-page tcp(7) that returns amount of unsent data in socket buffers. If I understand kernel code right, all the non-ACKed data is counted as "unsent". The ioctl is available at least since 2.4.x. Is there anything alike for {Free,Net,Open,*}BSD, Solaris, Windows? 回答1: There are (at least) two different pieces of information you might want: the amount of data that hasn't been sent yet, and the amount of data that's been sent-but-not-ACK-ed. On Linux:

问题 Linux has ioctl SIOCOUTQ described in man-page tcp(7) that returns amount of unsent data in socket buffers. If I understand kernel code right, all the non-ACKed data is counted as "unsent". The ioctl is available at least since 2.4.x. Is there anything alike for {Free,Net,Open,*}BSD, Solaris, Windows? 回答1: There are (at least) two different pieces of information you might want: the amount of data that hasn't been sent yet, and the amount of data that's been sent-but-not-ACK-ed. On Linux:

问题 This previous answer does not work anymore since TCPStream does not have clone() anymore. 回答1: You can use try_clone to get multiple handles for the stream. 来源： https://stackoverflow.com/questions/35969943/how-to-read-and-write-to-a-tcpstream-simultaneously

问题 This previous answer does not work anymore since TCPStream does not have clone() anymore. 回答1: You can use try_clone to get multiple handles for the stream. 来源： https://stackoverflow.com/questions/35969943/how-to-read-and-write-to-a-tcpstream-simultaneously