Embedded Programming with Modern C++ Cookbook

How to do it...

We will create an application that reads the current time from the Real-Time Clock (RTC) connected to the Raspberry Pi board:

1. In your ~/test working directory, create a subdirectory called rtc.
2. Use your favorite text editor to create a rtc.cpp file in the rtc subdirectory.
3. Let's put the required include functions into the rtc.cpp file:

#include <iostream>#include <system_error>#include <time.h>#include <unistd.h>#include <fcntl.h>#include <sys/ioctl.h>#include <linux/rtc.h>

4. Now, we define a class called Rtc that encapsulates the communication to the real-clock device:

class Rtc {  int fd;  public:    Rtc() {      fd = open("/dev/rtc", O_RDWR);      if (fd < 0) {        throw std::system_error(errno,            std::system_category(), "Failed to open RTC ...