getting an integer from a file c++

Question

How can I read a number from a file using fread fwrite This is my code

char *buff[1];
int highscore;
FILE *FPtr;
FPtr = fopen("highscore.txt","w+");
if(FPtr != NULL){
    fread(buff,sizeof(buff),1, FPtr);

}
if(buff == NULL){
     fprintf (FPtr, "%d" , 10);
     fclose(FPtr);
}

So after the initial running where it creates the file and prints 10 into the file I want to read the file and then print out the 10 How would I go about doing this??

Answer 1

If you're going to read an int with fread , you don't want to use a separate pointer, you want to use the address of that int :

int highscore;

fread(&highscore, sizeof(highscore), 1, score_file);

To match that, when you do the writing, you want to use fwrite :

int highscore;

fwrite(&highscore, sizeof(highscore), 1, score_file);

Beware, however, that the file won't be portable -- trying (for example) to write it on one machine and read it on another may produce grossly incorrect results. Even re-compiling your code with different options could change what the program's implicit idea of the file format (eg, changing from 32-bit to 64-bit compilation could easily break things).