关于boost asio的问题

Question

我有以下代码

#include <boost/date_time/posix_time/posix_time.hpp>

#include <iostream>
#include <boost/asio.hpp>
using namespace std;
int main(int argc,char *argv[]) {

    boost::asio::io_service io;
    boost::asio::deadline_timer t(io,boost::posix_time::seconds(5));
    t.wait();
    std::cout<<" hello world\n";

    return 0;
}

，但我有以下错误列表，

/usr/bin/make -f nbproject/Makefile-Debug.mk SUBPROJECTS= .build-conf
make[1]: Entering directory `/home/david/NetBeansProjects/Boost'
/usr/bin/make  -f nbproject/Makefile-Debug.mk dist/Debug/GNU-Linux-x86/boost
make[2]: Entering directory `/home/david/NetBeansProjects/Boost'
mkdir -p build/Debug/GNU-Linux-x86
rm -f build/Debug/GNU-Linux-x86/main.o.d
g++    -c -g -MMD -MP -MF build/Debug/GNU-Linux-x86/main.o.d -o build/Debug/GNU-Linux-x86/main.o main.cpp
mkdir -p dist/Debug/GNU-Linux-x86
g++     -o dist/Debug/GNU-Linux-x86/boost build/Debug/GNU-Linux-x86/main.o  
build/Debug/GNU-Linux-x86/main.o: In function `__static_initialization_and_destruction_0':
/usr/include/boost/system/error_code.hpp:205: undefined reference to `boost::system::get_system_category()'
/usr/include/boost/system/error_code.hpp:206: undefined reference to `boost::system::get_generic_category()'
/usr/include/boost/system/error_code.hpp:211: undefined reference to `boost::system::get_generic_category()'
/usr/include/boost/system/error_code.hpp:212: undefined reference to `boost::system::get_generic_category()'
/usr/include/boost/system/error_code.hpp:213: undefined reference to `boost::system::get_system_category()'
build/Debug/GNU-Linux-x86/main.o: In function `error_code':
/usr/include/boost/system/error_code.hpp:312: undefined reference to `boost::system::get_system_category()'
build/Debug/GNU-Linux-x86/main.o: In function `boost::asio::error::get_system_category()':
/usr/include/boost/asio/error.hpp:218: undefined reference to `boost::system::get_system_category()'
build/Debug/GNU-Linux-x86/main.o: In function `~posix_thread':
/usr/include/boost/asio/detail/posix_thread.hpp:69: undefined reference to `pthread_detach'
build/Debug/GNU-Linux-x86/main.o: In function `boost::asio::detail::posix_thread::join()':
/usr/include/boost/asio/detail/posix_thread.hpp:77: undefined reference to `pthread_join'
build/Debug/GNU-Linux-x86/main.o: In function `~posix_tss_ptr':
/usr/include/boost/asio/detail/posix_tss_ptr.hpp:61: undefined reference to `pthread_key_delete'
build/Debug/GNU-Linux-x86/main.o: In function `posix_tss_ptr':
/usr/include/boost/asio/detail/posix_tss_ptr.hpp:47: undefined reference to `pthread_key_create'
collect2: ld returned 1 exit status
make[2]: *** [dist/Debug/GNU-Linux-x86/boost] Error 1
make[2]: Leaving directory `/home/david/NetBeansProjects/Boost'
make[1]: *** [.build-conf] Error 2
make[1]: Leaving directory `/home/david/NetBeansProjects/Boost'
make: *** [.build-impl] Error 2
BUILD FAILED (exit value 2, total time: 5s)

请帮忙发生了什么？

Answer 1

问题不在于您的代码，问题在于编译器（实际上是链接器）的设置。您需要链接到 Boost.System 和 pthread 库。通常，这是通过将 -lboost_system、-lpthread 传递到 Makefile 或最喜欢的 IDE 中的链接器选项来完成的。

Answer 2

您需要链接Boost.System库：-lboost_system
您还需要链接 pthreads lib：-lpthread

Answer 3

您需要右键单击项目根文件夹并选择属性。

从那里，您需要在左侧窗格中选择“链接器”，然后“库”选项字段就在那里。您需要浏览系统，直到找到 libboost_system.a 二进制文件。通常位于 /usr/local/lib。

如果您找不到所需的文件，则可能尚未编译这些库的源代码。查看 http://ubuntuforums.org/showthread.php?t=1180792 或boost tar 包中包含入门文档。

Answer 4

供以后遇到同样问题的人参考：
在netbeans中右键单击项目-->属性-> C++ 编译器，底部有一个用于在 -lboost_system 选项中传递“附加参数”的选项。注意：必须定义 -lboost_system 否则会出现错误