LinuxQuestions.org - sendto function call in UDP client program

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sendto function call in UDP client program

The following is the UDP client code I am using.

Code:

int sockfd;

struct sockaddr_in serv_addr;

sockfd = socket(PF_INET, SOCK_DGRAM, 0);

if(sockfd == -1)

{

        cout<<"unable to open the socket"<<endl;

        exit(1);

}

bzero(&serv_addr, sizeof(serv_addr));

serv_addr.sin_family = AF_INET;

serv_addr.sin_addr.s_addr = inet_addr("172.16.1.2");

serv_addr.sin_port = htons(9999);

if( sendto(sockfd,message,strlen(message)+1,0,(struct sockaddr *)&serv_addr,sizeof(serv_addr)) < 0 )

{

        cout<< "unable to write to the socket descriptor\n";

        exit(1);

}

close(sockfd);

Even the server is down, sendto function is not returning -1.
Instead, it is returning the length of the message as if it is success.

can any body please help me tracing the bug?

Sorry - not a bug.

UDP, as you probably know, is inherently "unreliable". The status simply means the message was sent - the protocol does *not* guarantee that a message sent is also a message received.