Simple TCP client connection (in C)

connect_to_server.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;
}