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远程下载文件，并将http 头信息存放内存中以及文件大小等相关信息：
1 #include2 #include 3 #include 4 #include 5 6 struct MemoryStruct { 7 char* memory; 8 size_t allsize; 9 };10 11 static size_t WriteMemoryCallback(void* contents, size_t _size, size_t nmemb, void* userp)12 {13 size_t realsize = _size * nmemb;14 struct MemoryStruct *mem = (struct MemoryStruct*)userp;15 16 mem->memory = (char*)realloc(mem->memory, mem->allsize + realsize + 1);17 if(mem->memory == NULL){18 printf("realloc error...\n");19 return 0;20 }21 22 memcpy(&(mem->memory[mem->allsize]), contents, realsize);23 mem->allsize += realsize;24 mem->memory[mem->allsize] = 0;25 26 return realsize;27 }28 29 30 size_t write_data(char* buffer, size_t size, size_t items, void* outstream)31 {32 int written = fwrite(buffer, size, items, (FILE*)(outstream));33 return written;34 }35 36 double get_download_size(char* url){37 CURL* curl;38 CURLcode res;39 double size = 0.0;40 int httpcode=0;41 FILE* fd = fopen("./aaa.txt", "wb+");42 char *type = (char*)malloc(32);43 struct MemoryStruct chunk;44 chunk.memory = (char*)malloc(1);45 chunk.allsize = 0;46 47 48 49 curl = curl_easy_init();50 curl_easy_setopt(curl, CURLOPT_URL, url);51 //curl_easy_setopt(curl, CURLOPT_NOBODY, 1L);52 curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 0); //不跳转53 curl_easy_setopt(curl, CURLOPT_CONNECTTIMEOUT_MS, 3000);54 curl_easy_setopt(curl, CURLOPT_WRITEDATA, (void*)fd);55 curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_data);56 57 curl_easy_setopt(curl, CURLOPT_HEADERFUNCTION, WriteMemoryCallback);58 curl_easy_setopt(curl, CURLOPT_HEADERDATA, (void*)&chunk);59 60 res = curl_easy_perform(curl);61 if(res != CURLE_OK){62 fprintf(stderr, "curl_easy_getinfo() failed: %s\n", curl_easy_strerror(res));63 }64 res = curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE, &httpcode);65 if(res != CURLE_OK || httpcode != 200 ){66 fprintf(stdout, "httpcode error!\n"); 67 }68 res = curl_easy_getinfo(curl, CURLINFO_CONTENT_LENGTH_DOWNLOAD, &size);69 if(res != CURLE_OK ){70 fprintf(stdout, "httpcode xxxerror!\n"); 71 }72 73 res = curl_easy_getinfo(curl, CURLINFO_CONTENT_TYPE, &type);74 if(res != CURLE_OK ){75 fprintf(stdout, "TYPE xxxerror!\n"); 76 }77 printf("type:\n%s\n", type);78 printf("header:\n%s\n", chunk.memory);79 fclose(fd);80 free(chunk.memory); 81 curl_easy_cleanup(curl);82 83 return size;84 }85 86 int main(int argc, char* argv[])87 {88 char url[] = "http://www.fastcgi.com/dist/fcgi.tar.gz";89 90 double filesize = get_download_size(url);91 printf("[%0.0lf] %s\n", filesize, url);92 return 0;93 }
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