I set the server.sin_port=0 and then I call the bind function that doesn't return any error:
Where can I get the port that was asigned by the bind function?
Code:int sd; //server descriptor struct sockaddr_in server; bzero(&server,sizeof(server)); server.sin_family=AF_INET; server.sin_addr.s_addr=htonl(INADDR_ANY); server.sin_port=htons(0); if(bind(sd,(struct sockaddr*)&server,sizeof(struct sockaddr))==-1); // error printf("%d\n",ntohs(server.sin_port)); //is still 0
Have you read bind description?
For TCP/IP, if the port is specified as zero, the service provider assigns a unique port to the application with a value between 1024 and 5000. The application can use getsockname after calling bind to learn the address and the port that has been assigned to it. If the Internet address is equal to INADDR_ANY, getsockname cannot necessarily supply the address until the socket is connected, since several addresses can be valid if the host is multihomed.
All problems in computer science can be solved by another level of indirection,
except for the problem of too many layers of indirection.
– David J. Wheeler
what happend to the itoa(..) function in unix ?
This function is not standard - unix has nothing to do with it...Originally Posted by spank
use sprintf
All problems in computer science can be solved by another level of indirection,
except for the problem of too many layers of indirection.
– David J. Wheeler
Don't use bzero -- it's been obsolete for decades. It makes you look like a stupid hacker (I'm not saying you are one -- but let me guess, you've been learning socket programming by reading hacking sites, right?) Use memset() instead.
Also, why do you need to know the port number? Why are you binding without specifying the port, anyway?
