Programming

Can anyone help? I'm trying to write a program which will write to a socket. I can get the server to run, but always get an error when I try to connect.

It gives me an error at the "connect" command.

It's probably a simple error, but I can't seem to find it.



#include <sys/socket.h>
#include <netinet/in.h>
#include <sys/types.h>
#include <string.h>
#include <stdio.h>
#include <unistd.h>

int main(int argc, char* argv[]) {

int outgoing, newSock, i;
struct sockaddr_in sad;
char buf;
char action[255];
FILE *command;

if(argc < 4) {
printf("Wrong command line arguments");
return 1;
}

outgoing=socket(PF_INET,SOCK_STREAM,0);
if(outgoing == -1) {
printf("Unable to create socket");
return 1;
}

sad.sin_family=AF_INET;
sad.sin_port=atoi(argv[2]);
sad.sin_addr.s_addr=inet_addr(argv[1]);

if(connect(outgoing, (struct sockaddr *) &sad, sizeof(struct sockaddr_in)) == -1) {
printf("Cannot connect to address %s port %s", argv[1], argv[2]);
return 1;
}

send(outgoing, argv[3], strlen(argv[3]), 0);
while(recv(outgoing, &buf, 1, 0))
printf("%c", buf);

return 0;

}

Let's try a wild guess, you are using a little-endian machine such as a x86?

unsigned short my_port=atoi(argv[2]);

memset(&sad,0,sizeof(sad));
sad.sin_family=AF_INET;
sad.sin_port=htons(my_port);
sad.sin_addr.s_addr=inet_addr(argv[1]);

as long as both port and host are numeric, else use getservbyname and gethostbyname.

I'm using Solaris.

1. That doesn't indicate whether it's big endian or little as Solaris runs on both SPARC and x86.

2. Put "perror("connect") in the path immediately following a failed connect.

3. Do netstat -a on the target machine and confirm that there really is a LISTEN on the port you are trying to connect to.

4. before the connect() do the following

printf("connect(%s:%d)\n",
inet_ntoa(sad.sin_addr),ntohs(sad.sin_port));

Hi,
apart from the previous solutions given to u.
one thing i want to add if u are still facing some error
then please use these options at the time of compilations
-lnsl -lsocket -lresolv and i hope then u r program will work fine.

Please follow the rules and use full words. Cyberchat style of writing is not allowed.

Thanks everyone for the help. After some wrestling with it, it started working. Apparently there was no server listening.

Steve