#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 <accountistd.h>

#define SA struct sockaddr

#define MAXLINE 4096

#define MAXSUB  2000

#define MAXPARAM 2048

#define LISTENQ         1024

//线上线下接口宏开关

#define ONLINE 

extern int h_errno;

int sockfd;

char *hostname = "118.178.16.150";

char *send_sms_uri = "/send/json";

char *query_balance_uri = "/balance/json";

/**

 * * 发http post请求

 * */

ssize_t http_post(char *page, char *poststr)

{

    char sendline[MAXLINE + 1], recvline[MAXLINE + 1];

    ssize_t n;

         snprintf(sendline, MAXSUB,

                   "POST %s HTTP/1.1\r\n"

                   "Host: intapi.253.com\r\n"

                   "Content-type: application/json\r\n"

                   "Content-length: %zu\r\n\r\n"

                   "%s", page, strlen(poststr), poststr);

                   //, page, poststr);

    write(sockfd, sendline, strlen(sendline));

         printf("\n%s", sendline);

         printf("\n--------------------------\n");

    while ((n = read(sockfd, recvline, MAXLINE)) > 0) {

        recvline[n] = '\0';

        printf("%s\n", recvline);

    }

    return n;

}

/**

 * * 查账户余额

 * */

ssize_t get_balance(char *account, char *password)

{

    char params[MAXPARAM + 1];

    char *cp = params;

         sprintf(cp,"{\"account\":\"%s\",\"password\":\"%s\"}", account, password);

    return http_post(query_balance_uri, cp);

}

/**

 * * 发送短信

 * */

ssize_t send_sms(char *account, char *password, char *mobile, char *msg)

{

    char params[MAXPARAM + 1];

    char *cp = params;

         sprintf(cp,"{\"account\":\"%s\",\"password\":\"%s\",\"mobile\":\"%s\",\"msg\":\"%s\"}", account, password, mobile, msg);   

    return http_post(send_sms_uri, cp);

}

int main(void)

{

    struct sockaddr_in servaddr;

    char str[50];

    //建立socket连接

    sockfd = socket(AF_INET, SOCK_STREAM, 0);

    bzero(&servaddr, sizeof(servaddr));

    servaddr.sin_addr.s_addr = inet_addr(hostname);

    servaddr.sin_family = AF_INET;

    servaddr.sin_port = htons(80);

    inet_pton(AF_INET, str, &servaddr.sin_addr);

    connect(sockfd, (SA *) & servaddr, sizeof(servaddr));

         char *account = "";

         char *password = "a.123456987";

         //手机号码，格式(区号+手机号码)，例如：8615800000000，其中86为中国的区号

         char *mobile = "8615800000000";

         //必须带签名

         char *msg = "【253云通讯】您的验证码是123400";

    //get_balance(account, password);

    send_sms(account, password, mobile, msg);

    close(sockfd);

    exit(0);

}

原文链接：http://www.apkbus.com/blog-947460-77853.html