#include "../util/Timer.hpp" #include <atomic> #include <functional> #include <iostream> #include <thread> #include <pthread.h> using namespace std; class SpinLock { public: SpinLock () { _flag.store(false); } bool TryLock() { bool expect = false; return _flag.compare_exchange_weak(expect, true); } void Lock() { bool expect = false; while(!_flag.compare_exchange_weak(expect, true)) expect = false; } void UnLock() { _flag.store(false); } private: atomic<bool> _flag; }; pthread_spinlock_t g_lock = 0; void func(int &arg, int total) { while(total-- > 0) { pthread_spin_lock(&g_lock); ++arg; pthread_spin_unlock(&g_lock); } } SpinLock g_lock2; void func2(int &arg, int total) { while(total-- > 0) { g_lock2.Lock(); ++arg; g_lock2.UnLock(); } } const int kAddNum = 1000000; const int kRoundNum = 100; int main() { pthread_spin_init(&g_lock, PTHREAD_PROCESS_PRIVATE); Timer t; t.TimerBeg(); for(int i = 0; i < kRoundNum; i++) { int value = 0; thread a(func, ref(value), kAddNum); thread b(func, ref(value), kAddNum); a.join(); b.join(); } t.TimerEnd(); cout << t << endl; t.TimerBeg(); for(int i = 0; i < kRoundNum; i++) { int value2 = 0; thread c(func2, ref(value2), kAddNum); thread d(func2, ref(value2), kAddNum); c.join(); d.join(); } t.TimerEnd(); cout << t << endl; return 0; }

https://www.youtube.com/watch?v=bWH-nL7v5F4

oh , multi threading is a hell

Why won't you use a real app instead of a website?

multi threading before c++11 is wild west

im learning multithreading in ansi C

https://www.cs.kent.ac.uk/projects/ofa/c++csp/

🤦‍♀It is not a website, it is a tutorial. It is showing how to use gdb on Mac and Linux, to debug problems with code, when code compiled with gcc.

Oh OK sorry

🤓Thanks Barney. What made you think it was a website? Are you doing development on a Mac or Linux machine?

No, usually when I'm not home I'm using GDB website, I thought you were talking about that..

Can you share the web link please? Why don't you use it natively?

@andrew1923 the patterno doesn't work 😏

Hi guys. just a part of holy wars but where you put asterisk for a pointer type? int* ptr or int *ptr ? 😂

Hi guys. just a part of holy wars but where you put asterisk for a pointer type? int* ptr or int *ptr ? 😂

Hi guys. just a part of holy wars but where you put asterisk for a pointer type? int* ptr or int *ptr ? 😂

void * buffer; *smacks table*

int*p; because every symbol costs 😂

int*p; because every symbol costs 😂

😞💔

🥺💔

Both are right

Well then pray for a miracle or you just work on the questions and send your work to the group so we can help correct your errors

Basically, int* ptr; means for you pointer is a type modifier int *ptr; means for you pointer is a variable modifier

this can be misleading tho, when a is a pointer but b is not. So it's not really the type that's modified. int* a, b;

hey folks, ive been using linux for years now and its a part of my everyday job. I want to get into systems programming but I want to understand the internals before i go there. For example, there are lots of guides on "socket programming with c++ / python and what not", but it doesn't actually help if one doesn't know what a socket really is and what they're trying to build. I've looked at "the linux programming interface" books but I can't understand why would you use certain sys calls and so on. This may sound a little confusing because i am a bit confused myself. Are there any good systems programming books that go into the details of everything?

freecodecamp.org

Hey everyone I want learn C language Can anyone suggest any free good course on YouTube or any other platforms?

How i can do linked list on c

What?