Reading/Writing floats from/to files

[CactusCat]

How can I read and write float values to and from a file (using fopen, fwrite etc.)

Ideally each float value would take up 4 bytes on the file, but I'm not sure how to do this. Can anyone help?

[MikeyD]

open the files in binary-mode (b-flag).
then use fwrite to write it unformatted to Your file.

Mikey

[jim mcnamara]

#include <stdio.h>

int main(){
        FILE *fp;
        float f=99;
        int i;
        fp=fopen("test.dat","wb");
        for (i=0;i<100;i++){
            f++;
            fwrite(&f,sizeof(float),1,fp);
        }
        fclose(fp);
        fp=fopen("test.dat","rb");
        while (!feof(fp)){
            if(fread(&f,sizeof(float),1,fp)>0) printf("%f\n",f);
        }
        fclose(fp);
	return 0;
}