【发布时间】：2017-07-05 23:16:27
【问题描述】：
我正在尝试设置一个 Http 客户端并使用here 显示的示例下载一些数据。
当我尝试运行该程序时，它显示“conf.h”未找到。
$g++ -std=c++11 BingSearch.cpp
In file included from BingSearch.cpp:1:
In file included from /usr/local/include/cpprest/http_client.h:53:
In file included from /usr/local/include/boost/asio/ssl.hpp:19:
In file included from /usr/local/include/boost/asio/ssl/context.hpp:27:
In file included from /usr/local/include/boost/asio/ssl/context_base.hpp:19:
/usr/local/include/boost/asio/ssl/detail/openssl_types.hpp:20:10: fatal error: 'openssl/conf.h' file not found
#include <openssl/conf.h>
^
1 error generated.
我查看了其他 SO posts 并设置了必要的路径变量。
$echo $LDFLAGS
-L/usr/local/opt/openssl/lib
$echo $CPPFLAGS
-I/usr/local/opt/openssl/include
$echo $PKG_CONFIG_PATH
/usr/local/opt/openssl/lib/pkgconfig
conf.h 也位于 openssl 目录中
openssl $find /usr/local/opt/openssl/ -name "conf.h"
/usr/local/opt/openssl//include/openssl/conf.h
编译下面的文件还需要做些什么吗？它来自here。
#include <cpprest/http_client.h>
#include <cpprest/filestream.h>
using namespace utility; // Common utilities like string conversions
using namespace web; // Common features like URIs.
using namespace web::http; // Common HTTP functionality
using namespace web::http::client; // HTTP client features
using namespace concurrency::streams; // Asynchronous streams
int main(int argc, char* argv[])
{
auto fileStream = std::make_shared<ostream>();
// Open stream to output file.
pplx::task<void> requestTask = fstream::open_ostream(U("results.html")).then([=](ostream outFile)
{
*fileStream = outFile;
// Create http_client to send the request.
http_client client(U("http://www.bing.com/"));
// Build request URI and start the request.
uri_builder builder(U("/search"));
builder.append_query(U("q"), U("cpprestsdk github"));
return client.request(methods::GET, builder.to_string());
})
// Handle response headers arriving.
.then([=](http_response response)
{
printf("Received response status code:%u\n", response.status_code());
// Write response body into the file.
return response.body().read_to_end(fileStream->streambuf());
})
// Close the file stream.
.then([=](size_t)
{
return fileStream->close();
});
// Wait for all the outstanding I/O to complete and handle any exceptions
try
{
requestTask.wait();
}
catch (const std::exception &e)
{
printf("Error exception:%s\n", e.what());
}
return 0;
}
【问题讨论】：
-
"编译这个文件还需要做些什么吗？" : 我们怎么知道你不给我们看“这个文件”？请发帖minimal reproducible example。
-
它与github.com/Microsoft/cpprestsdk/wiki/Getting-Started-Tutorial 的文件相同 抱歉，我错过了添加代码，因为我添加了一个包含完整代码的链接。
-
你能解释一下投反对票的原因吗？
-
请显示用于编译程序或库的命令行。
CPPFLAGS是 C 预处理器。您应该将-I/usr/local/opt/openssl/include添加到CFLAGS（C 选项）和CXXFLAGS（C++ 选项）。将参数向下传递给 C 预处理器是编译器驱动程序的工作；反之亦然。如果字面上是g++ -std=c++11 BingSearch.cpp，则使用g++ $CXXFLAGS -std=c++11 BingSearch.cpp
标签： c++ macos openssl casablanca cpprest-sdk