[demo] write file circularly

exceed 1G Then write back

#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <time.h>

struct timespec interval = {0,10};
char *a = "1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890";
char *c = "qwertyuiopqwertyuiopqwertyuiopqwertyuiopqwertyuiopqwertyuiopqwertyuiopqwertyuiopqwertyuiopqwertyuiop";

int main(int argc,char** agrv)
{
	long offset = 0;
	constexpr long oneGB = 1024*1024*1024;
	
	FILE* f = fopen("./loopwrite_test","wb+");
	
	while(1){
		offset = ftell(f);
		if(offset>=oneGB){
			rewind(f);
			a = c;
		}
		fwrite(a,100,1,f);
		fflush(f);
		//nanosleep(&interval,NULL);
	}
}