binary file again

Hi all,

I need to read a binary file as a string and store it into a buffer to do some stuff, but when i run my program i got some strange characters.

Here is my program:

Code:

int
main (int argc, char **argv)
{
   FILE                *in;
   char                head_string[5];
   int                 j;
   char                buffer[512];

   in = fopen(argv[1], "rb");

   if(in == NULL) {
       fprintf (stderr, "Can't open file.\n");
       return EXIT_FAILURE;
   }

   while (fgets(buffer, sizeof(buffer), in) != NULL) {
       for (j = 0; j < 5 ; j++)
               head_string[j] = buffer[j];
       printf("The length of the block is : %s\n", head_string);         
   }          

   fclose(in);

   return 0;
}

When i run my program (passing a binary file as a parameter) i got a strange chars:

Code:

$ ./a.out log_dump.data
The length of the header is : )
The length of the header is : ????
The length of the header is : S%a0
The length of the header is : ?????
The length of the header is : ?????
The length of the header is : ?????
The length of the header is : ?????
The length of the header is : ?????
The length of the header is : ?????
The length of the header is : ?????
The length of the header is : ?????
The length of the header is : ?????
The length of the header is : ?????
The length of the header is : ?????
The length of the header is : ?????
The length of the header is : ?????
The length of the header is : )
The length of the header is : ????
The length of the header is : SF0i

the display of my file using an hex dump:

Code:

0500    0033    5100    f100    ffff    00ff    0000    0000
0000    0000    0000    0000    0000    0000    0001    ffff
ffff    ffff    ffff    ffff    ffff    00ff    00ff    0500
f008    ff01    f008    ff01    0002    4233    0219    0912
ff20    5343    5049    3130    2020    ffff    ffff    ffff
ffff    0506    2926    0007    fff0    ffff    ffff    ffff
0000    4900    0101    2122    0000    4900    328a    ca41
0002    0033    5100    f100    ffff    ffff    0000    4200
2117    0100    1400    53f2    6125    0030    3921    33f0
9371    7372    fff2    ffff    00ff    4207    2117    0100
1400    53f8    4606    6930    9477    06f0    9371    9372

Thanks for your help.