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@Josh798
Created August 14, 2020 21:56
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Simple TCP client connection (in C)
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
/**
* Returns a file descriptor of a socket connected to the specified
* address, or returns -1 if an error occurred.
*/
int connect_to_server(const char *ip_address, unsigned short port)
{
int sockfd;
struct sockaddr_in servaddr;
sockfd = socket(AF_INET, SOCK_STREAM, 0);
if (sockfd == -1)
{
fprintf(stderr, "Could not create socket. %s.\n", strerror(errno));
return -1;
}
memset(&servaddr, 0, sizeof(servaddr));
servaddr.sin_family = AF_INET;
if (inet_aton(ip_address, &(servaddr.sin_addr)) == 0)
{
fprintf(stderr, "Could not parse IP address."); // inet_aton() does not set errno.
close(sockfd);
return -1;
}
servaddr.sin_port = htons(port);
if (connect(sockfd, (struct sockaddr*)&servaddr, sizeof(servaddr)) != 0)
{
fprintf(stderr, "Could not connect to server. %s.\n", strerror(errno));
close(sockfd);
return -1;
}
return sockfd;
}
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