B46_File_binary_mode.c

#include <stdio.h>
#include <math.h>
#define MAX 30

int main(void)
{
	setbuf(stdout,NULL);
	char *fileName = "myArray.txt";
	double a[MAX] ;
	int i;
	for(i = 0 ; i < MAX ;i++)
	{
		a[i] = sqrt(i);
	}
	FILE *fout = fopen(fileName,"wb");
	if(fout == NULL) exit(-1);
	fwrite(a,sizeof(double) ,MAX , fout);
	fclose(fout);

	FILE *fin = fopen(fileName,"rb");
	if(fin == NULL) exit(-1);
	double b[MAX];
	fread( b, sizeof(double), MAX , fin );

	for(i = 0 ; i < MAX ;i++)
		{
			printf("%d : %f\n",i,b[i]);
		}
	fclose(fin);

	return 0;
}