#include <stdio.h> /* printf, sprintf */
#include <stdlib.h> /* exit */
#include <unistd.h> /* read, write, close */
#include <string.h> /* memcpy, memset */
#include <sys/socket.h> /* socket, connect */
#include <netinet/in.h> /* struct sockaddr_in, struct sockaddr */
#include <netdb.h> /* struct hostent, gethostbyname */
void error(const char *msg) { perror(msg); exit(0); }
int main(int argc,char *argv[])
{ /* first what are we going to send and where are we going to send it? */ int portno = 80; char *host = "api.somesite.com"; char *message_fmt = "POST /apikey=%s&command=%s HTTP/1.0\r\n\r\n"; struct hostent *server; struct sockaddr_in serv_addr; int sockfd, bytes, sent, received, total; char message[1024],response[4096]; if (argc < 3) { puts("Parameters: <apikey> <command>"); exit(0); } /* fill in the parameters */ sprintf(message,message_fmt,argv[1],argv[2]); printf("Request:\n%s\n",message); /* create the socket */ sockfd = socket(AF_INET, SOCK_STREAM, 0); if (sockfd < 0) error("ERROR opening socket"); /* lookup the ip address */ server = gethostbyname(host); if (server == NULL) error("ERROR, no such host"); /* fill in the structure */ memset(&serv_addr,0,sizeof(serv_addr)); serv_addr.sin_family = AF_INET; serv_addr.sin_port = htons(portno); memcpy(&serv_addr.sin_addr.s_addr,server->h_addr,server->h_length); /* connect the socket */ if (connect(sockfd,(struct sockaddr *)&serv_addr,sizeof(serv_addr)) < 0) error("ERROR connecting"); /* send the request */ total = strlen(message); sent = 0; do { bytes = write(sockfd,message+sent,total-sent); if (bytes < 0) error("ERROR writing message to socket"); if (bytes == 0) break; sent+=bytes; } while (sent < total); /* receive the response */ memset(response,0,sizeof(response)); total = sizeof(response)-1; received = 0; do { bytes = read(sockfd,response+received,total-received); if (bytes < 0) error("ERROR reading response from socket"); if (bytes == 0) break; received+=bytes; } while (received < total); /* * if the number of received bytes is the total size of the * array then we have run out of space to store the response * and it hasn't all arrived yet - so that's a bad thing */ if (received == total) error("ERROR storing complete response from socket"); /* close the socket */ close(sockfd); /* process response */ printf("Response:\n%s\n",response); return 0;
}