假设我有一个类如
class c {
// ...
void *print(void *){ cout << "Hello"; }
}
然后我有一个c的向量
vector<c> classes; pthread_t t1;
classes.push_back(c());
classes.push_back(c());
现在,我想创建一个线程 c.print();
以下是给我以下问题: pthread_create(&t1, NULL, &c[0].print, NULL);
错误输出:无法将'void*(tree_item :: )(void)'转换为'void*()(void)'以将参数'3'转换为'int pthread_create(pthread_t*,const pthread_attr_t*,void*()(void),void*)'
我想知道启动一个C++类成员的pthread 的最佳方法是什么？我自己的方法作为答案......
我已经像这样创建了MutexCondition类
/*MutexCondtion.h file*/
#ifndef MUTEXCONDITION_H_
#define MUTEXCONDITION_H_
#include <pthread.h>
#include <stdio.h>
class MutexCondition {
private:
bool init();
bool destroy();
protected:
pthread_mutex_t m_mut;
pthread_cond_t m_con;
public:
MutexCondition(){
init();
}
virtual ~MutexCondition(){
destroy();
}
bool lock();
bool unLock();
bool wait();
bool signal();
};
#endif /* MUTEXCONDITION_H_ */
MutexCondtion.cpp文件
#include "MutexCondition.h"
bool MutexCondition::init(){
printf("MutexCondition::init called\n");
pthread_mutex_init(&m_mut, NULL);
pthread_cond_init(&m_con, NULL);
return true;
}
bool MutexCondition::destroy(){
pthread_mutex_destroy(&m_mut);
pthread_cond_destroy(&m_con);
return true;
}
bool MutexCondition::lock(){
pthread_mutex_lock(&m_mut);
return true;
}
bool MutexCondition::unLock(){
pthread_mutex_unlock(&m_mut);
return true;
}
bool MutexCondition::wait(){ …我刚刚开始学习C++,我正在尝试使Thread类具有Java Thread类的基本功能.我正在尝试做的是创建一个你继承的类,编写一个Run方法(在基类中是纯虚拟的)创建一个子类的对象,在它上面调用start方法并且你有线程.
问题是,在我使用C++的方式中,调度没有正确完成 - 就像Run函数不是虚函数一样,调用了基类的Run方法.
这是标题的代码
#ifndef _THREAD_H_
#define _THREAD_H_
#include <pthread.h>
class Thread {
public:
Thread();
void Start();
~Thread();
protected:
virtual void Run() = 0;
private:
static void *RunWrapper(void *);
pthread_t thread;
};
#endif
实施
#include "thread.h"
#include <pthread.h>
Thread::Thread() {
}
void Thread::Start() {
pthread_create(&thread, NULL, Thread::RunWrapper, (void *) this);
}
void *Thread::RunWrapper(void *arg) {
Thread *t = (Thread *) arg;
t->Run();
return arg;
}
Thread::~Thread() {
pthread_join(thread, NULL);
}
而实际上试图做某事的文件
#include <iostream>
#include "thread.h"
class MyThread : …可能重复:
来自类的pthread函数
我有这个代码,由于这pthread_create行代码我无法编译:
void* gtk_functor::_threaded_run(void* win)
{
Gtk::Window* w = static_cast<Gtk::Window*>(win);
Gtk::Main::run(*w);
delete w;
}
void gtk_functor::operator ()(Gtk::Window& win, bool threaded)
{
if (threaded)
{
pthread_t t_num;
pthread_create(&t_num, NULL, (void* (*)(void*))>k_functor::_threaded_run, static_cast<void*>(&win));
}
else
{
Gtk::Main::run(win);
}
}
这个gcc线:
g++ -o main 'pkg-config --cflags --libs sqlite3 gtkmm-3.0' -lpthread main.cpp
最后用这个输出编译:
code/ui.cpp: In member function 'void ui::gtk_functor::operator()(Gtk::Window&, bool)':
code/ui.cpp:45:65: warning: converting from 'void* (ui::gtk_functor::*)(void*)' to 'void* (*)(void*)' [-Wpmf-conversions]
显然代码不能正常工作,我得到sementation fault了if (threaded)提升.
我知道它与演员,但我不知道将成员函数传递给pthread_create的正确形式.有什么建议？
我创建了一个包含声明的widget.h文件pthread_function,我想destroyWidget在widget.cpp中该类Widget 的成员函数中调用它.但总是显示错误.我将展示.cpp和.h文件.
widget.h文件
class Widget
{
public:
Widget();
void createWidget(int x,int y,int w,int h);
void showWidget();
int wid;
pthread_t thread;
int *incomingval,id;
void join();
Window win;
XEvent evt;
private:
void* destroyWidget(void* ptr);
Display *disp;
int screenNumber;
unsigned long white;
unsigned long black;
long eventMask;
GC gc;
int tbit;
int *incoming,val;
};
现在是widget.cpp
Widget::Widget()
{
disp=XOpenDisplay( NULL );
screenNumber=DefaultScreen(disp);
white=WhitePixel(disp,screenNumber);
black=BlackPixel(disp,screenNumber);
eventMask=StructureNotifyMask;
tbit=0;
}
void Widget::createWidget(int x,int y,int w,int h)
{
wid=w;
win= XCreateSimpleWindow(disp,DefaultRootWindow(disp),x,y,w,h,1,white,black);
}
void Widget::showWidget() …假设我有以下课程:
*.h:
class MyClass{
void caller();
int threadProcuder(void *args);
};
*cpp:
void MyClass::caller()
{
pthread_t i;
pthread_create(&i,NULL,(void*(*)(void*))&MyClass::threadProcedure,(void*)this);
}
int MyClass::threadProcedure(void *args)
{
cout << "body of thread" << endl;
}
不幸的是,线程没有运行.