RFComm- client while loop does not end when server is killed - c

Question

I am using RFComm socket. I have a client loop where it does read and write in a loop. When the server exits I guess , the client should also terminate. But client is not terminating. It is not printing "client loop exited". My code is as follows-
void* clientLoop(void* arg)
{
char* server_address = (char*)arg;
printf("\nserver address in clientLoop = %s\n",server_address);
struct sockaddr_rc addr = { 0 };
int s, status;
char gpsMessage[128];
int flag = true;
struct timeval tv;
// allocate a socket
s = socket(AF_BLUETOOTH, SOCK_STREAM, BTPROTO_RFCOMM);
if(s<0) perror("socket error in client loop");
// set the connection parameters (who to connect to)
addr.rc_family = AF_BLUETOOTH;
addr.rc_channel = (uint8_t) 1;
str2ba( server_address, &addr.rc_bdaddr );
tv.tv_sec = 30; // 30 seconds
tv.tv_usec = 0; // microsecs, set to 0 (or ...)
setsockopt(s, SOL_SOCKET, SO_RCVTIMEO, (const char*)&tv,sizeof(struct timeval));
// connect to server
status = connect(s, (struct sockaddr *)&addr, sizeof(addr));
if(status<0) perror("socket status error in client loop");
// send a message
if( status == 0 ) {
while(flag)
{
sleep(10);
printf("clientLoop did not exited\n");
prepareMessageToSend(gpsMessage);
status = write(s,gpsMessage , strlen(gpsMessage));
if(status == 0) flag=false;
status = read(s,gpsMessage, 128);
if(strcmp(gpsMessage,"Ring"))
{
printf("RING\n");
system("espeak -ven+f3 -k5 -s150 \"I've just picked up a fault in the AE35 unit\"");
}
if(status == 0) flag=false;
}
}
if( status < 0 ) perror("uh oh");
printf("clientLoop exited\n");
close(s);
//return s;
}

Answer 1

Give the socket a timeout
struct timeval tv;
tv.tv_sec = 30; // 30 seconds
tv.tv_usec = 0; // microsecs, set to 0 (or ...)
setsockopt(s, SOL_SOCKET, SO_RCVTIMEO, (const char*)&tv,sizeof(struct timeval));
if the read cannot be performed within that time, the timeout is triggered.
Also
status = read(s,gpsMessage, 128);
// check status first, or if there is no ambiguity, check only the 4 first chars
if(strncmp(gpsMessage, "Ring", 4))
(in case the message could not be set correctly)