How to pass socket to a loop

[fblau]

I want to have the following process:

1. create socket to server
2. loop
send data to socket
end loop

I can't figure out how to pass the int socket into the loop module

#include "eHealth.h"
#include "ecg.h"
#include <iostream>
#include <fstream>
#include <sstream>
#include <cstring>
#include <sys/socket.h>
#include <sys/types.h>
#include <netdb.h>

void setup(){

int status;
int socketfd;

struct addrinfo host_info;
struct addrinfo *host_info_list;

memset(&host_info, 0, sizeof(host_info));

host_info.ai_family=AF_INET;
host_info.ai_socktype=SOCK_STREAM;

status=getaddrinfo("192.168.0.112", "6001", &host_info, &host_info_list);
if (status==-1) std::cout << "getaddrinfo error";

socketfd=socket(host_info_list->ai_family, host_info_list->ai_socktype,host_info_list->ai_protocol);
if (socketfd==-1) std::cout << "socket error";

status=connect(socketfd, host_info_list->ai_addr, host_info_list->ai_addrlen);
if (status==-1) std::cout << "connect error";
}
// The loop routine runs over and over again forever:
void loop() {
  extern int socketfd;
  float ECG = eHealth.getECG();

  
  std::ostringstream ostr;
  ostr<<ECG;
  std::string ECGmsg=ostr.str();

  int len;
  std::string msg=ECGmsg+" \n";

  int bytes_sent;
  len=strlen(msg.c_str());
  bytes_sent=send(socketfd,msg.c_str(),len,0);

  delay(250);
}

int main (){
	setup();
	while(1){
		loop();
	}
	return (0);
}

[coder777]

let setup() return the socketfd and pass that as a parameter to loop():

int setup(){

int status;
int socketfd;

...

return socketfd;
}
// The loop routine runs over and over again forever:
void loop(int socketfd) {
  extern int socketfd;
...
}

int main (){
	int socketfd = setup();
	while(1){
		loop(socketfd);
	}
	return (0);
}