Http POST with C

ref: Here_sourceforge

#include <arpa/inet.h>
#include <assert.h>
#include <errno.h>
#include <netinet/in.h>
#include <signal.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/wait.h>
#include <netdb.h>
#include <unistd.h>

#define SA      struct sockaddr
#define MAXLINE 4096
#define MAXSUB  200
#define LISTENQ 1024

extern int h_errno;

ssize_t process_http(int sockfd, char *host, char *page, char *poststr)
{
 char sendline[MAXLINE + 1], recvline[MAXLINE + 1];
 ssize_t n;
 snprintf(sendline, MAXSUB,
   "POST %s HTTP/1.0\r\n"
   "Host: %s\r\n"
   "Content-type: application/x-www-form-urlencoded\r\n"
   "Content-length: %d\r\n\r\n"
   "%s", page, host, strlen(poststr), poststr);

 write(sockfd, sendline, strlen(sendline));
 while ((n = read(sockfd, recvline, MAXLINE)) > 0) {
  recvline[n] = '\0';
  printf("%s", recvline);
 }
 return n;
}
int main(void)
{
 int sockfd;
 struct sockaddr_in servaddr;
 char **pptr;
 char *hname = "souptonuts.sourceforge.net";
 char *page = "/chirico/test.php";
 char *poststr = "mode=login&user=test&password=test\r\n";
 char str[50];
 struct hostent *hptr;

 if ((hptr = gethostbyname(hname)) == NULL) {
  fprintf(stderr, " gethostbyname error for host: %s: %s",
   hname, hstrerror(h_errno));
  exit(1);
 }
 printf("hostname: %s\n", hptr->h_name);
 if (hptr->h_addrtype == AF_INET
     && (pptr = hptr->h_addr_list) != NULL) {
  printf("address: %s\n",
         inet_ntop(hptr->h_addrtype, *pptr, str,
     sizeof(str)));
 } else {
  fprintf(stderr, "Error call inet_ntop \n");
 }

 sockfd = socket(AF_INET, SOCK_STREAM, 0);
 bzero(&servaddr, sizeof(servaddr));
 servaddr.sin_family = AF_INET;
 servaddr.sin_port = htons(80);
 inet_pton(AF_INET, str, &servaddr.sin_addr);

 connect(sockfd, (SA *) & servaddr, sizeof(servaddr));
 process_http(sockfd, hname, page, poststr);
 close(sockfd);
 exit(0);
}

ref: Here_sourceforge