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bind() system call
hey ive copied an example from a tutorial
and i wanted to know why this is working
but putting an error on bind? (the error
is "invalid argument")
Code:
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#define MYPORT 3490 // the port users will be connecting to
#define BACKLOG 2 // how many pending connections queue will hold
int main()
{
int sockfd, new_fd; // listen on sock_fd, new connection on new_fd
struct sockaddr_in my_addr; // my address information
struct sockaddr_in their_addr; // connector's address information
int sin_size;
sockfd = socket(AF_INET, SOCK_STREAM, 0); // do some error checking!
my_addr.sin_family = AF_INET; // host byte order
my_addr.sin_port = htons(MYPORT); // short, network byte order
my_addr.sin_addr.s_addr = INADDR_ANY; // auto-fill with my IP
memset(&(my_addr.sin_zero), '\0', 8); // zero the rest of the struct
// don't forget your error checking for these calls:
bind(sockfd, (struct sockaddr *)&my_addr, sizeof(struct sockaddr));
if(bind(sockfd, (struct sockaddr *)&my_addr, sizeof(struct sockaddr)) == -1)
perror("bind");
listen(sockfd, BACKLOG);
if(listen(sockfd, BACKLOG) == -1)
perror("listen");
sin_size = sizeof(struct sockaddr_in);
new_fd = accept(sockfd, (struct sockaddr *)&their_addr, &sin_size);
if(accept(sockfd, (struct sockaddr *)&their_addr, &sin_size) == -1)
perror("accept");
return 0;
}
how would i rewrite this to see who is loggin on, when someone connects?
thanks
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Why have you doubled up all the system calls? You have two calls to bind(), two to listen() etc etc
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oh right thanks! fixed that..the error is gone.
but what have i to add if i want to see when someones logges on?
cya
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Read the rest of Beej's guide ;)
printf("server: got connection from %s\n", inet_ntoa(their_addr.sin_addr));
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