This post is just supposed to be my personal note. But I will be happy if this can help you in some way!
# macOS brew install libomp cmake # Ubuntu/Debian sudo apt-get install -y libomp-dev cmakeContinue reading Compile LLVM with OpenMP on macOS and Linux
之前在写优化后的Sieve of Eratosthenes筛法时，写了一个函数用于计算另一个给定函数的执行时间，但是还不够通用，今天用C++11写了一个通用的版本。
#include <chrono> #include <functional> #include <future> #include <stdio.h> #include <type_traits> /** * @brief Give the elapsed time of any function * * @param func_name Used in printf * @param func The function that to be measured * @param args Arguments of the given function * * @return The return value of the given function */ template <class Function, class ... Args> std::future<typename std::result_of<Function(Args...)>::type> runtime(const char * func_name, Function&& func, Args&&... args) { typedef typename std::result_of<Function(Args...)>::type return_type; typedef std::packaged_task<return_type()> task; auto t = std::make_shared<task>(std::bind(std::forward<Function>(func), std::forward<Args>(args)...)); auto start = chrono::high_resolution_clock::now(); auto ret = t->get_future(); { (*t)(); } auto end = chrono::high_resolution_clock::now(); printf("%s: %lfs\n", func_name, ((chrono::duration<double>)((end - start))).count()); return ret; }
@import Darwin.sys.mount; int main(int argc, const char * agrv[]) { struct statfs buf; long long freespace = 0; if(statfs("/", &buf) >= 0){ freespace = (long long)buf.f_bsize * buf.f_blocks; } if(statfs("/private/var", &buf) >= 0){ freespace += (long long)buf.f_bsize * buf.f_blocks; } printf("%lld\n",freespace); }