libcurl sample program

来自http://tunps.com/libcurl-sample-program

#define CURL_STATICLIB
#define _CRT_SECURE_NO_WARNINGS
#define _CRT_SECURE_NO_DEPRECATE 
#pragma comment(lib,"ws2_32.lib")
#pragma comment(lib,"D:\\win32dev\\curl-7.19.0\\lib\\Debug\\curllib.lib")
/* Start of test program */
#include <stdio.h>
#include <stdlib.h> 

#include <curl/curl.h>
#include <curl/types.h>
#include <curl/easy.h>

size_t write_data(void *ptr, size_t size, size_t nmemb, FILE *stream)
{
	static int first_time=1;
	char outfilename[FILENAME_MAX] = "body.html";
	static FILE *outfile;
	size_t written;
	if (first_time) {
		first_time = 0;
		outfile = fopen(outfilename,"w+");
		if (outfile == NULL) {
			return -1;
		}
		fprintf(stderr,"The body is <%s>\n",outfilename);
	}
	written = fwrite(ptr,size,nmemb,outfile);
	return written;
}

int main(int argc, char **argv)
{
	CURL *curl_handle;
	char headerfilename[FILENAME_MAX] = "head.html";
	FILE *headerfile;
	int rc=0;
	curl_handle = curl_easy_init();
	curl_easy_setopt(curl_handle,   CURLOPT_URL, "http://www.sina.com.cn");
	curl_easy_setopt(curl_handle,   CURLOPT_NOPROGRESS  ,1); 
	curl_easy_setopt(curl_handle,   CURLOPT_WRITEFUNCTION,&write_data);
	headerfile = fopen(headerfilename,"w");
	if (headerfile == NULL) {
		curl_easy_cleanup(curl_handle);
		return -1;
	}
	curl_easy_setopt(curl_handle,   CURLOPT_WRITEHEADER ,headerfile);
	curl_easy_perform(curl_handle);
	printf("The head is <%s>\n",headerfilename);
	fclose(headerfile);
	curl_easy_cleanup(curl_handle);
	return 0;
}
/* End of test program */

将获取的html文件内容保存在body.html。保存的方法是curl_easy_setopt函数中设置CURLOPT_WRITEFUNCTION的回调函数为write_data。

在write_data这个回调函数中需要注意的是，curl碰到web文件过大的情况会分段获取内容

size_t write_data(void *ptr, size_t size, size_t nmemb, FILE *stream)