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C++ pass function as argument

void retrieveTime5(char *dtValue);
void showTime6();
void passFunc(void(*funcName)());

int main()
{
    passFunc(&showTime6);
    return 0;
}

void passFunc(void(*funcName)())
{
    chrono::time_point<chrono::system_clock> startTime;
    chrono::time_point<chrono::system_clock> endTime;
    startTime
=chrono::system_clock::now(); printf("Started in passFunc!\n"); (*funcName)(); endTime=chrono::system_clock::now(); printf("Ended in passFunc!\n"); cout<<"Time cost:" <<chrono::duration_cast<chrono::seconds>(endTime-startTime).count()<<" seconds," <<chrono::duration_cast<chrono::milliseconds>(endTime-startTime).count()<<"
milliseconds," <<chrono::duration_cast<chrono::microseconds>(endTime-startTime).count()<<" microseconds," <<chrono::duration_cast<chrono::nanoseconds>(endTime-startTime).count()<<" nanoseconds."<<endl; } void showTime6() { char *dtValue=(char*)malloc
(20); for(int i=0;i<10;i++) { retrieveTime5(dtValue); printf("Index=%d,value=%s\n",i,dtValue); sleep(1); } free(dtValue); } void retrieveTime5(char *dtValue) { time_t rawTime = time(NULL); struct tm tmInfo = *localtime(&rawTime); strftime(dtValue, 20, "%Y%m%d%H%M%S", &tmInfo); }

Declare

void passFunc(void(*funcName)());

Implement

void passFunc(void(*funcName)())
{ 
    (*funcName)(); 
}

Invoke

int main()
{
    passFunc(&showTime6);
    return 0;
}