c++ multithreading synchronization

Here is a simplified version of my problem. There are N threads executing following 3 instructions in an infinite loop: A -> B -> C -> A -> B -> C -> A -> B -> ....... I want that all threads execute instruction B concurrently ie execution of B by any thread should start only if all threads have reached B. So, if there is a thread that has executed B -> C -> A, i

c ++多线程同步

这是我的问题的简化版本。 在无限循环中有3个指令执行N个线程: A -> B -> C -> A -> B -> C -> A -> B -> ....... 我希望所有的线程同时执行指令B,即任何线程的B执行都应该在所有线程都到达B时才启动。因此,如果有一个线程执行了B - > C - > A,它应该在此等待,直到其他线程线程也准备执行B. 如果可能的话,请让我知道一个便携式解决方案,可以在Windows和MAC上运行。 您应该检查Boos

Is it possible to use Boost.Format with a preallocated buffer?

I was wondering whether Boost.Format does support using a fixed-width / preallocated buffer as output instead of a dynamic buffer managed by the lib itself? That is, normally you'd do: boost::format myfmt("arg1: %1% / arg2: %2%"); // e.g.: cout << (myfmt % 3.14 % 42); // or string s = boost::str( myfmt % "hey!" % "there!"); so the Boost:Format lib will automatically take care of all

是否有可能使用预分配缓冲区的Boost.Format?

我想知道Boost.Format是否支持使用固定宽度/预分配的缓冲区作为输出,而不是由lib本身管理的动态缓冲区? 也就是说,通常你会这样做: boost::format myfmt("arg1: %1% / arg2: %2%"); // e.g.: cout << (myfmt % 3.14 % 42); // or string s = boost::str( myfmt % "hey!" % "there!"); 因此Boost:Format lib将自动处理分配足够的空间并为您管理“输出缓冲区”。 我想知道是否有任何方法使用Boost.Format预定义的非

nanosleep() call from Lua script paused QT GUI thread

I am developing a test tool to generate waveform from PC parallel port. This tools is designed to generate any pattern of waveform with timing accuracy of ms, so I use Lua script to define the waveform pattern, the GUI start new QThread to run the script when user clicks [Start] button. The following three functions for Lua are implemented as C++ global functions: pwrite: write data to paral

来自Lua脚本的nanosleep()调用暂停了QT GUI线程

我正在开发一个测试工具来从PC并行端口生成波形。 这个工具被设计用于生成任意波形模式,其定时精度为ms,所以我使用Lua脚本来定义波形模式,当用户单击[Start]按钮时,GUI启动新的QThread来运行脚本。 Lua的以下三个函数被实现为C ++全局函数: 写入:将数据写入并行端口。 msleep:等待某个ms(使用nanosleep()实现) 打印:覆盖Lua的默认打印功能,这一个将附加消息到一个QTextEdit小部件。 当调用pwrite时,写

Using Likely() / Unlikely() Preprocessor Macros in if

If I have: #define likely(x) __builtin_expect((x),1) #define unlikely(x) __builtin_expect((x),0) if (A) return true; else if (B) return false; ... else if (Z) return true; else //this will never really happen!!!! raiseError(); return false; Can I put likely() around the last condition check like else if (likely(Z)) to signify that the final statement (else) is

在if中使用可能()/不可能()预处理器宏

如果我有: #define likely(x) __builtin_expect((x),1) #define unlikely(x) __builtin_expect((x),0) if (A) return true; else if (B) return false; ... else if (Z) return true; else //this will never really happen!!!! raiseError(); return false; else if (likely(Z))表示最终语句(else)非常不可能,那么我是否可以将最后一个条件检查放在可能的位置? else if (likely(Z))

Multiple Inheritance from two derived classes

I have an abstract base class which acts as an interface. I have two "sets" of derived classes, which implement half of the abstract class. ( one "set" defines the abstract virtual methods related to initialization, the other "set" defines those related to the actual "work". ) I then have derived classes which use multiple inheritance to construct full

来自两个派生类的多重继承

我有一个作为接口的抽象基类。 我有两组派生类,它们实现了抽象类的一半。 (一个“set”定义了与初始化有关的抽象虚拟方法,另一个“set”定义与实际“work”相关的抽象虚拟方法。) 然后我有派生类使用多重继承来构造完全定义的类(并且本身不添加任何东西)。 所以:(坏的伪代码) class AbsBase { virtual void init() = 0; virtual void work() = 0; } class AbsInit : public AbsBase { void init() { do_this(); }

How do I find the location of the executable in C?

This question already has an answer here: Finding current executable's path without /proc/self/exe 12 answers To summarize: On Unixes with /proc really straight and realiable way is to: readlink("/proc/self/exe", buf, bufsize) (Linux) readlink("/proc/curproc/file", buf, bufsize) (FreeBSD) readlink("/proc/self/path/a.out", buf, bufsize) (Solaris) On

我如何在C中找到可执行文件的位置?

这个问题在这里已经有了答案: 在没有/ proc / self / exe的情况下查找当前可执行文件的路径12个答案 总结: 在使用/proc Unix上,真正直接和可行的方法是: readlink("/proc/self/exe", buf, bufsize) (Linux) readlink("/proc/curproc/file", buf, bufsize) (FreeBSD) readlink("/proc/self/path/a.out", buf, bufsize) (Solaris) 在没有/proc Unix上(即如果以上失败):

How to create threads with Win32 API?

I have written a TCP server with Win32 API and C++ but it's single-threaded. Can anyone tell me how would I go about making it multi-threaded? I imagine for every new accepted connection, I'd have to spawn a thread that takes care of it. But I have never had experience with threading in Win32. Can anyone tell me how I would go about threaded programming with Win32 and C++? Read the

如何使用Win32 API创建线程?

我用Win32 API和C ++编写了一个TCP服务器,但它是单线程的。 任何人都可以告诉我如何使它成为多线程? 我想象每一个新的接受的连接,我必须产生一个线程来照顾它。 但我从来没有在Win32中使用线程的经验。 任何人都可以告诉我如何使用Win32和C ++进行线程编程吗? 阅读以下文件: CreateThread函数 你也可以在我的答案中看到一个例子: 多线程在c ++中 在c ++中运行类成员函数的线程

Making code (more) cross platform

I am trying to make my (currently working on windows) code a bit more platform independent. This small snippet is for opening a text file (for reading/writing). As with modern pcs many files are stored as unicode. Now In this question I am especially wondering what the right way to open such a file is. (Where the filename may be unicode). On windows, using microsoft visual studio, I used

使代码(更多)跨平台

我试图让我的(当前在windows上工作)代码更独立一些。 这个小片段用于打开文本文件(用于阅读/写作)。 与现代PC一样,许多文件都以unicode存储。 现在在这个问题中,我特别想知道打开这样的文件的正确方法是什么。 (其中文件名可能是unicode)。 在Windows上,我使用了微软的Visual Studio char* filename("c:\xD0x92.txt"); #ifdef _WIN32 std::wstring_convert<std::codecvt_utf8_utf16<wchar_t>> conv

How to open unicode file with ifstream using mingw under Windows?

Please note this is not the same questions as How to open an std::fstream (ofstream or ifstream) with a unicode filename?. That question was about an unicode filename , this one is about an unicode file contents . I need to open a UTF-8 unicode file (containing Spanish characters) with an ifstream. Under Linux this is no problem, but under Windows it is. bool OpenSpanishFile(string filename)

如何在Windows下使用mingw打开ifstream文件的unicode文件?

请注意,这与使用unicode文件名打开std :: fstream(ofstream或ifstream)不同。 这个问题是关于一个unicode 文件名 ,这个是关于一个unicode文件的内容 。 我需要用ifstream打开一个UTF-8 unicode文件(包含西班牙文字符)。 在Linux下这是没有问题的,但是在Windows下它是。 bool OpenSpanishFile(string filename) { ifstream spanishFile; #ifdef WINDOWS spanishFile.open(filename.c_str(),ios::binary);

Read/Write file with unicode file name with plain C++/Boost

I want to read / write a file with a unicode file name using boost filesystem, boost locale on Windows (mingw) (should be platform independent at the end). This is my code: #include <boost/locale.hpp> #define BOOST_NO_CXX11_SCOPED_ENUMS #include <boost/filesystem.hpp> #include <boost/filesystem/fstream.hpp> namespace fs = boost::filesystem; #include <string> #include &

使用纯C ++ / Boost读取/写入带unicode文件名的文件

我想使用boost文件系统读取/写入一个带unicode文件名的文件,在Windows上使用boost语言环境(mingw)(最后应该与平台无关)。 这是我的代码: #include <boost/locale.hpp> #define BOOST_NO_CXX11_SCOPED_ENUMS #include <boost/filesystem.hpp> #include <boost/filesystem/fstream.hpp> namespace fs = boost::filesystem; #include <string> #include <iostream> int main() { std::l