boost::thread简介和gdb调试线程

File:

#include <boost/thread/thread.hpp>

class thread
{
public:
    class attributes; // EXTENSION

    thread() noexcept;
    thread(const thread&) = delete;
    thread& operator=(const thread&) = delete;

    thread(thread&&) noexcept;
    thread& operator=(thread&&) noexcept;
    ~thread();

    template <class F>
    explicit thread(F f);
    template <class F>
    thread(F &&f);

    template <class F,class A1,class A2,...>
    thread(F f,A1 a1,A2 a2,...);
    template <class F, class ...Args>
    explicit thread(F&& f, Args&&... args);

    template <class F>
    explicit thread(attributes& attrs, F f); // EXTENSION
    template <class F>
    thread(attributes& attrs, F &&f); // EXTENSION
    template <class F, class ...Args>
    explicit thread(attributes& attrs, F&& f, Args&&... args);

    // move support
    thread(thread && x) noexcept;
    thread& operator=(thread && x) noexcept;

    void swap(thread& x) noexcept;

    class id;

    id get_id() const noexcept;

    bool joinable() const noexcept;
    void join();
    template <class Rep, class Period>
    bool try_join_for(const chrono::duration<Rep, Period>& rel_time); // EXTENSION
    template <class Clock, class Duration>
    bool try_join_until(const chrono::time_point<Clock, Duration>& t); // EXTENSION

    void detach();

    static unsigned hardware_concurrency() noexcept;

    typedef platform-specific-type native_handle_type;
    native_handle_type native_handle();

    void interrupt(); // EXTENSION
    bool interruption_requested() const noexcept; // EXTENSION


#if defined BOOST_THREAD_USES_DATETIME
    bool timed_join(const system_time& wait_until); // DEPRECATED
    template<typename TimeDuration>
    bool timed_join(TimeDuration const& rel_time); // DEPRECATED
    static void sleep(const system_time& xt);// DEPRECATED
#endif

#if defined BOOST_THREAD_PROVIDES_THREAD_EQ
    bool operator==(const thread& other) const; // DEPRECATED
    bool operator!=(const thread& other) const; // DEPRECATED

#endif
    static void yield() noexcept; // DEPRECATED

};

void swap(thread& lhs,thread& rhs) noexcept;

//具体提供的接口可以参考boost参考文档

namespace boost {
  class thread;
  class thread_group;
}

从名字可以看出来，thread为封装线程使用的对象，thread_group为线程组使用的对象

简单举例说明：

void Run()
{
	prctl(PR_SET_NAME,(unsigned long)"yx");	
	cout<<"thread:yx"<<endl;
    sleep(100);
}

boost::thread th(Run);
th.join();

//这里顺便设置了下线程名词，具体可参考系统调用prctl，使用比较简单，这里不再介绍
yixiao@yixiao-p6-1319cx:/proc/2840$ ps -ef|grep -i a.out|grep -v grep

yixiao    3186  2101  0 22:05 pts/1    00:00:00 ./a.out

yixiao@yixiao-p6-1319cx:/proc/3186$ ps -L -p 3186
  PID   LWP TTY          TIME CMD
 3186  3186 pts/1    00:00:00 a.out
 3186  3187 pts/1    00:00:00 yx

thread_group的使用也较为简单：

void Run1()
{
	prctl(PR_SET_NAME,(unsigned long)"yx_1");	
	cout<<"thread:yx_1"<<endl;
    sleep(100);
}

boost::thread_group gp;
gp.create_thread(Run);
gp.add_thread(new boost::thread(Run1));
gp.join_all();

yixiao@yixiao-p6-1319cx:/proc/3186$ ps -ef|grep -i a.out|grep -v grep
yixiao    3552  2101  0 22:10 pts/1    00:00:00 ./a.out

yixiao@yixiao-p6-1319cx:/proc/3186$ ps -L -p 3552
  PID   LWP TTY          TIME CMD
 3552  3552 pts/1    00:00:00 a.out
 3552  3553 pts/1    00:00:00 yx
 3552  3554 pts/1    00:00:00 yx_1

gdb调试线程：

基本命令：

info threads                      --显示当前可调试的所有进程
thread ID                         --切换当前调试的线程为指定ID的线程
thread apply ID1 ID2 command      --让一个或多个线程执行GDB的命令command
thread apply all command          --让所有被调试线程执行GDB命令command
set scheduler-locking off|on|step 
 -off  不锁定任何进程，所有线程都执行
 -on   只有当花钱被调试程序会执行
 -step 在单步的时候，除了next过一个函数的情况外，只有当前线程会执行

(gdb) info threads
  Id   Target Id         Frame 
  3    Thread 0x7ffff65d0700 (LWP 3696) "a.out" 0x00007ffff73df3c1 in clone () from /lib/x86_64-linux-gnu/libc.so.6
* 2    Thread 0x7ffff6dd1700 (LWP 3695) "a.out" Run () at test_thread.cc:10
  1    Thread 0x7ffff7fdf740 (LWP 3692) "a.out" 0x00007ffff73df3c1 in clone () from /lib/x86_64-linux-gnu/libc.so.6

(gdb) thread 2
[Switching to thread 2 (Thread 0x7ffff6dd1700 (LWP 3695))]
#0  Run () at test_thread.cc:10
10 prctl(PR_SET_NAME,(unsigned long)"yx");

(gdb) thread apply all continue


Thread 3 (Thread 0x7ffff65d0700 (LWP 3696)):
Continuing.
thread:yx


Breakpoint 1, Run1 () at test_thread.cc:17
17 prctl(PR_SET_NAME,(unsigned long)"yx_1");


Thread 2 (Thread 0x7ffff6dd1700 (LWP 3695)):
Continuing.