hi all ,
i am working on TCP Socket Programming.
i need to Print the Port no on which the client is connected in Sever Program,
when i am Trying to Print the Port no which is a field of sockaddr_in structure, that is an argument of accept call in server.
but its not printing what we are passing in client.it is printing some incremental value.
the code looks as follows.
Server Program :
int main (int argc, char *argv[]) {
int sd, cliLen, optval,optlen,newSd;
struct sockaddr_in cliAddr, servAddr;
char line[MAX_MSG];
/* create socket */
sd = socket(AF_INET, SOCK_STREAM, 0);
if(sd<0) {
perror("cannot open socket ");
return ERROR;
}
/* bind server port */
servAddr.sin_family = AF_INET;
servAddr.sin_addr.s_addr = htonl(INADDR_ANY);
servAddr.sin_port = htons(SERVER_PORT);
if(bind(sd, (struct sockaddr *) &servAddr, sizeof(servAddr))<0) {
perror("cannot bind port ");
return ERROR;
}
optval= 1;
optlen= sizeof(optval);
if(setsockopt(sd, SOL_SOCKET, SO_REUSEADDR , &optval, optlen) < 0)
printf("Cannot setsockopt SO_REUSEADDR\n");
listen(sd,5);
while(1)
{
printf("%s: waiting for data on port TCP %u\n",argv[0],SERVER_PORT);
cliLen = sizeof(cliAddr);
newSd = accept(sd, (struct sockaddr *) &cliAddr, &cliLen);
if(newSd<0)
{
perror("cannot accept connection ");
return ERROR;
}
printf("Acept Fd is %d\n",newSd);
/* init line */
memset(line,0x0,MAX_MSG);
/* receive segments */
while(read_line(newSd,line)!=ERROR)
{
printf("%s: received from %s:TCP%d : %s\n", argv[0], inet_ntoa(cliAddr.sin_addr), ntohs(cliAddr.sin_port), line);
/* init line */
memset(line,0x0,MAX_MSG);
} /* while(read_line) */
} /* while (1) */
}
here in the above code when we are printing the port value with the use of ntohs(cliAddr.sin_port)
the value what we are getting is some incremntal value.
can any one solve this problem
thanks a lottt
################################################
Client Program :
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <stdio.h>
#include <unistd.h> /* close */
#define SERVER_PORT 1500
#define MAX_MSG 100
int main (int argc, char *argv[]) {
int sd, rc, i;
struct sockaddr_in localAddr, servAddr;
if(argc < 2) {
printf("usage: %s <data1> <data2> ... <dataN>\n",argv[0]);
exit(1);
}
/* h = gethostbyname(argv[1]);
if(h==NULL) {
printf("%s: unknown host '%s'\n",argv[0],argv[1]);
exit(1);
}
*/
bzero(&servAddr,sizeof(servAddr));
servAddr.sin_family = AF_INET;
servAddr.sin_addr.s_addr = inet_addr("3.209.134.204");
servAddr.sin_port = htons(20000);
printf("######### %u #########\n",ntohs(servAddr.sin_port));
/* create socket */
sd = socket(AF_INET, SOCK_STREAM, 0);
if(sd<0) {
perror("cannot open socket ");
exit(1);
}
/* bind any port number */
/* localAddr.sin_family = AF_INET;
localAddr.sin_addr.s_addr = htonl(INADDR_ANY);
localAddr.sin_port = htons(0);
rc = bind(sd, (struct sockaddr *) &localAddr, sizeof(localAddr));
if(rc<0) {
printf("%s: cannot bind port TCP %u\n",argv[0],SERVER_PORT);
perror("error ");
exit(1);
}
*/
/* connect to server */
rc = connect(sd, (struct sockaddr *) &servAddr, sizeof(servAddr));
if(rc<0) {
perror("cannot connect ");
exit(1);
}
for(i=1;i<argc;i++) {
rc = send(sd, argv[i], strlen(argv[i]) + 1, 0);
if(rc<0) {
perror("cannot send data ");
close(sd);
exit(1);
}
printf("%s: data%u sent (%s)\n",argv[0],i-1,argv[i]);
}
return 0;
}
