Ubuntu18.04.2 amd64编译安装libcurl支持https

1.准备工作，安装ssl库：

sudo apt-get install openssl
sudo apt-get install libssl-dev

2.下载libcurl源代码：

wget https://curl.haxx.se/download/curl-7.65.3.tar.xz

3.解压并进入源代码目录：

tar xf curl-7.65.3.tar.xz
cd curl-7.65.3

4.配置编译选项：

./configure --prefix=/usr                           
            --disable-static                        
            --enable-threaded-resolver              
            --with-ca-path=/etc/ssl/certs

5.编译：

make

6.安装（需要root权限）：

make install &&

rm -rf docs/examples/.deps &&

find docs ( -name Makefile* -o -name *.1 -o -name *.3 ) -exec rm {} ; &&

install -v -d -m755 /usr/share/doc/curl-7.65.3 &&
cp -v -R docs/*     /usr/share/doc/curl-7.65.3

至此，编译安装完成。

写代码测试一下：

#include <stdio.h>
#include <curl/curl.h>
 
int main(void)
{
  CURL *curl;
  CURLcode res;
 
  curl_global_init(CURL_GLOBAL_DEFAULT);
 
  curl = curl_easy_init();
  if(curl) {
    curl_easy_setopt(curl, CURLOPT_URL, "https://www.baidu.com/");
 
    /* Perform the request, res will get the return code */
    res = curl_easy_perform(curl);
    /* Check for errors */
    if(res != CURLE_OK)
      fprintf(stderr, "curl_easy_perform() failed: %s
",
              curl_easy_strerror(res));
 
    /* always cleanup */
    curl_easy_cleanup(curl);
  }
 
  curl_global_cleanup();
 
  return 0;
}

编译：

gcc hello_https.c -l curl -o hello_https

运行：

./hello_https

运行结果截图：

 附 自定义回调处理响应数据代码：

#include <stdio.h>
#include <curl/curl.h>

static size_t write_data(void *ptr, size_t size, size_t nmemb, void *stream)
{
    if(stream == NULL) 
    return 0;
    printf("%s", ptr);
    return size * nmemb;
}

int main(void)
{
  CURL *curl;
  CURLcode res;
 
  curl_global_init(CURL_GLOBAL_DEFAULT);
 
  curl = curl_easy_init();
  if(curl) {
    curl_easy_setopt(curl, CURLOPT_URL, "https://www.baidu.com/");
    curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_data);
 
    /* Perform the request, res will get the return code */
    res = curl_easy_perform(curl);
    /* Check for errors */
    if(res != CURLE_OK)
      fprintf(stderr, "curl_easy_perform() failed: %s
",
              curl_easy_strerror(res));
 
    /* always cleanup */
    curl_easy_cleanup(curl);
  }
 
  curl_global_cleanup();
 
  return 0;
}