Question

I was under the impression that to open binary files using strings, you could simply create the string, and then implement it as the name of the file where it will read the string. This is what my lecture notes state. However I’m obveously missing something. I’ve used &name, name, &name[SIZE] within the fopen and each time i’ve gotten inBinFile == NULL unless I use the commented line. My string is correct. What’s wrong? Help is much appreciated. Thanks in advance.

#include <stdio.h>  
#include <stdlib.h> 
#define SIZE 25

int frstmenu(void);  
int sndmenu(void);  

int main()  
{  

    int fmenu, smenu;  
    char name[SIZE];  
    FILE *inBinFile;    
    unsigned char numRead;

  fmenu = frstmenu();
  if ( fmenu !=1 && fmenu !=2 )
  {
        printf("\nIncorrect option\n");
        fmenu = frstmenu();
  }

  if (fmenu == 1)
  {    
       printf("\nEnter the file name: \n");
       scanf("%s", &name[SIZE]);
       /* printf("filename: %s", &name[SIZE]); */

       smenu = sndmenu();

       if (smenu !=1 && smenu !=2 )
       {
           printf("\nIncorrect option\n");
           smenu = sndmenu();
       }
       if (smenu == 1)
       {            

           inBinFile = fopen( name, "rb");
        /* inBinFile = fopen( "stream.grc", "rb"); */

        if (inBinFile == NULL)
        {
          fprintf(stderr, "Error opening %s", &name[SIZE]);
          return(-1);

        fclose(inBinFile);
       }      
  }
  return(0);
}

int frstmenu()
{

  float selection;

  printf("----Menu----\n");
  printf("1 Open a file ( supported format: .grc )\n"); 
  printf("2 Exit the program\n");
  printf("  Please select an option (1 or 2): ");
  scanf("%f", &selection);

  return(selection);

}

int sndmenu()

{

int selection;

 printf("---Menu---\n");
 printf("1 Decode the sequence\n");
 printf("2 Exit the program\n");
 printf("  Please select an option (1 or 2):\n");
 scanf("%i", &selection);

 return(selection);
}

Answer 1

You probably want to say

scanf("%s", &name[0]);

or even just:

scanf("%s", name);

Your &name[SIZE] points to name + SIZE, which is beyond the allocated memory.