c++ - 编译错误 : "‘function’ in namespace ‘std’ does not name a template type"

Question

我正在尝试使用 libtins 嗅探我的网络流量图书馆。于是我下载了tar.gz库，并顺利完成了手册中提到的所有库编译步骤。

现在，我正在尝试编译我的第一个示例程序:

  1 #include <iostream>
  2 #include <tins/tins.h>
  3 
  4 using namespace Tins;
  5 
  6 bool callback(const PDU &pdu) {
  7     const IP &ip = pdu.rfind_pdu<IP>(); // Find the IP layer
  8     const TCP &tcp = pdu.rfind_pdu<TCP>(); // Find the TCP layer
  9     std::cout << ip.src_addr() << ':' << tcp.sport() << " -> "
 10               << ip.dst_addr() << ':' << tcp.dport() << std::endl;
 11     return true;
 12 }
 13 
 14 int main() {
 15     Sniffer("eth0").sniff_loop(callback);
 16 }  

当我想编译它时，我遇到了以下错误:

me@me-MS-7693:~/Desktop/Workspace/cpp_libtins$ g++ main.cpp -ltins
In file included from /usr/local/include/tins/tins.h:60:0,
                 from main.cpp:2:
/usr/local/include/tins/crypto.h:297:18: error: ‘function’ in namespace ‘std’ does not name a template type
     typedef std::function<void(const std::string&,
                  ^
/usr/local/include/tins/crypto.h:308:18: error: ‘function’ in namespace ‘std’ does not name a template type
     typedef std::function<void(const std::string&,
                  ^
/usr/local/include/tins/crypto.h:401:44: error: ‘handshake_captured_callback_type’ does not name a type
     void handshake_captured_callback(const handshake_captured_callback_type& callback);
                                            ^
/usr/local/include/tins/crypto.h:412:34: error: ‘ap_found_callback_type’ does not name a type
     void ap_found_callback(const ap_found_callback_type& callback);
                                  ^
/usr/local/include/tins/crypto.h:445:9: error: ‘handshake_captured_callback_type’ does not name a type
         handshake_captured_callback_type handshake_captured_callback_;
         ^
/usr/local/include/tins/crypto.h:446:9: error: ‘ap_found_callback_type’ does not name a type
         ap_found_callback_type ap_found_callback_;
         ^
me@me-MS-7693:~/Desktop/Workspace/cpp_libtins$ 

怎么了？

---

我的编译器版本:

me@me-MS-7693:~/Desktop/Workspace/cpp_libtins$ g++ --version
g++ (Ubuntu 5.4.0-6ubuntu1~16.04.2) 5.4.0 20160609
Copyright (C) 2015 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

me@me-MS-7693:~/Desktop/Workspace/cpp_libtins$ 

Answer 1

因为你的 GCC 早于 6.0，你需要传递 -std=c++11 开关，otherwise it is in C++03 mode . C++03 没有 std::function。