Hi im writing a socket programmin code for a uni assn and always get an error msg when compiling.
Error message is: error: request for member ‘err’ in something not a structure or union
UDPclient.c:157: error: request for member ‘errStr’ in something not a structure or union
UDPclient.c:160: error: request for member ‘x’ in something not a structure or union
UDPclient.c:161: error: request for member ‘y’ in something not a structure or union
UDPclient.c:162: error: request for member ‘temp’ in something not a structure or union
UDPclient.c:163: error: request for member ‘tLeft’ in something not a structure or union
UDPclient.c:164: error: request for member ‘mLeft’ in something not a structure or union
UDPclient.c:184: error: request for member ‘mLeft’ in something not a structure or union
UDPclient.c:185: error: request for member ‘tLeft’ in something not a structure or union
Code:
#include <stdio.h>
#include <sys/socket.h> /* for socket(), connect(), sendto(), and recvfrom() */
#include <arpa/inet.h> /* for sockaddr_in and inet_addr() */
#include <stdlib.h> /* for atoi() and exit() */
#include <string.h> /* for memset() */
#include <unistd.h> /* for close() */
#include <strings.h>
#include <time.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <math.h>
#include <errno.h>
#include <assert.h>
#define SERV_PORT 31180 /* server UDP port */
#define SERV_IP "149.171.37.233" /* server IP Address */
#define GRID_SIZE 100 /* 100 x 100 grid */
#define PASSWD "thunt10" /* password in each packet */
#define MAX_MSG_LEN 64 /* max size of any msg */
#define MAX_TIME 120 /* time (seconds) limit for a game */
#define MAX_MOVES 100 /* mximum number of moves allowed */
#define MSG_REGISTER 1
#define MSG_MOVE 2
typedef struct {
char passwd[8]; /* password */
unsigned long mType; /* message type = MSG_REGISTER */
unsigned long id; /* student id */
unsigned short x, y; /* x and y co-ordinates of starting point */
} RegMsg_t;
typedef struct {
char passwd[8]; /* password */
unsigned long mType; /* message type = MSG_MOVE */
unsigned long id; /* student id */
char dir; /* direction: N, S, E, or W */
char pad[3]; /* padding for word-alignment */
} MoveMsg_t;
typedef struct {
unsigned long err; /* error code: 0 if all ok */
unsigned short x, y; /* x and y co-ordinates of current location */
long temp; /* temperature */
unsigned long tLeft; /* time left */
unsigned long mLeft; /* moves left */
char errStr[108]; /* error string */
} RespMsg_t;
int main(int argc, char *argv[]) {
int sock; /* Socket descriptor */
int e;
long err;
int inMsgLen;
//int outMsgLen;
char passwd[8];
long temp, tleft, mleft;
unsigned short x, y;
unsigned long mType, id;
//long ttaken, mtaken;
//char dir;
//char pad[3];
char inMsg[MAX_MSG_LEN];
//char outMsg[MAX_MSG_LEN];
struct sockaddr_in servAddr; /* Echo server address */
struct sockaddr_in fromAddr; /* Source address of echo */
RegMsg_t regmsg; /* Registration Message */
RespMsg_t *respmsg; /* Response Message from the Server */
//MoveMsg_t movmsg; /* Move Message */
//unsigned short echoServPort; /* Echo server port */
unsigned int fromSize; /* In-out of address size for recvfrom() */
unsigned short servPort = 31180; /* Server UDP port number */
char *servIP = "149.171.37.233"; /* IP address of server */
int regmsgLen; /* Length of Registration message */
int respStringLen; /* Length of received response */
/* GETTING REGISTER-MESSAGE PACKAGED & SENT */
if ((argc < 5) || (argc > 6)) { /* Test for correct number of arguments */
printf("Please enter <password> <message-type> <student-id> <x-location> <y-location>\n");
exit(1);
}
/* Scanning data from user input */
strcpy(passwd, argv[1]); /* First arg: password "thunt10" */
mType = atoi(argv[2]); /* Second arg: message-type */
id = atoi(argv[3]); /* Third arg: student-id */
x = atoi(argv[4]); /* Fourth arg: x-coordinate */
y = atoi(argv[5]); /* Fifth arg: y-coordinate */
regmsgLen = sizeof(regmsg);
/* Create a datagram/UDP socket */
if ((sock = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0) {
printf("socket() failed");
}
/* Construct the server address structure */
memset(&servAddr, 0, sizeof(servAddr)); /* Zero out structure */
servAddr.sin_family = AF_INET; /* Internet addr family */
servAddr.sin_addr.s_addr = inet_addr(servIP); /* Server IP address */
servAddr.sin_port = htons(servPort); /* Server port */
memset(®msg, 0, regmsgLen);
strcpy(regmsg.passwd, passwd);
regmsg.mType = htonl(mType);
regmsg.id = htonl(mType);
regmsg.x = htons(x);
regmsg.y = htons(y);
/* Send the string to the server */
if ((e = sendto(sock, (char *)®msg, regmsgLen, 0, (struct sockaddr *)&servAddr, sizeof(servAddr))) != regmsgLen) {
printf("sendto() sent a different number of bytes than expected");
}
else if (e < 0) {
printf("Error with sending\n");
exit(1);
}
/* RECEIVING A RESPONSE MESSAGE AFTER REGISTRATION */
fromSize = sizeof(fromAddr);
respStringLen = recvfrom(sock, (char *)&respmsg, MAX_MSG_LEN, 0, (struct sockaddr *)&fromAddr, &fromSize);
if (servAddr.sin_addr.s_addr != fromAddr.sin_addr.s_addr) {
fprintf(stderr,"Error: received a packet from unknown source.\n");
exit(1);
}
//respmsg = (RespMsg_t *)&inMsg;
err = ntohl(respmsg.err);
if (err != 0) {
printf("Registration failed.\n");
printf("%s\n", respmsg.errStr);
}
else {
x = ntohs(respmsg.x);
y = ntohs(respmsg.y);
temp = ntohl(respmsg.temp);
tleft = ntohl(respmsg.tLeft);
mleft = ntohl(respmsg.mLeft);
printf("SERVER RESPONSE:\n");
printf("x-location = %d\ty-location = %d\n", x, y);
printf("temperature = %ld\n", temp);
printf("time-left = %ld\n", tleft);
printf("moves-left = %ld\n", mleft);
}
return 0;
}