I’m slowly working my way through 30 odd examples of C code that I wrote for the first 20 chapters in my Ebook., And finding odd compile errors. Here’s an example.

I’ve rewritten my stopWatch object for high-precision timing. This is the header.

#include 

struct _stopWatch {
  struct timespec start; 
  struct timespec stop;
} stopWatch;

typedef struct _stopWatch stopWatch;

void startTimer(stopWatch *timer);
void stopTimer(stopWatch *timer);
double diff(stopWatch *timer);

It won’t compile, and keeps on complaining that timespec is an incomplete type. I saw one solution which was to redefine timespec like this:

struct timespec {
  time_t tv_sec; /* seconds */
  long tv_nsec; /* nanoseconds */
};

But that got Clang wound up about timespec redefined errors. I searched and searched and eventually found the answer. Instead of

#include <time>

Use this as well

#include <time> 
#include <linux/time.h>

Simple when you know how!