why fread does not work?

Hi~ every one~ i have a piece of code here, But it does no work for the fread function. Can any one help me to figure it out ? thank you~(in the 50th line)

Code:

---


 1 #include<stdio.h>
      2 #include<stdlib.h>
      3 #include<string.h>
      4
      5 typedef struct _HEADER {
      6
      7 int num1;
      8 int num2;
      9 int num3;
    10 int num4;
    11
    12 }HEADER;
    13
    14
    15 void readheader(HEADER *,FILE *);
    16 void writeheader(HEADER *,FILE *);
    17 short**** construct_4D(int dimension1, int dimension2, int dimension3, int dimension4);
    18
    19 int main(int argc,char *argv[])
    20 {
    21
    22
    23
    24 int i,j;
    25 HEADER header;
    26 short ****datatable;
    27
    28 datatable = (short ****)construct_4D(2,2,3,4);
    29
    30 /*if(argc  !=2){
    31 printf("Cannot open the file for read\n");
    32 }*/
    33
    34
    35 FILE *fp1=fopen(argv[1],"r");
    36 FILE *fp2=fopen("newdata.dat","w");
    37
    38  printf("The processing file is %s \n",argv[1]);
    39
    40  for (i=0;i<2;i++){
    41  for(j=0; j<2; j++){
    42  datatable[i][j] = (short **)construct_4D(2,2,3,4);
    43  }
    44  }
    45
    46
    47
    48 readheader(&header,fp1);
    49
    50 for(i=0; i<2 ;i++){
    51 for (j=0; j<4; j++)fread(&datatable[i][j][0][0],sizeof(short),6,fp1);
    52  }
    53  fclose( fp1 );
  54
    55  if ( fclose( fp1 ) == 0 )
    56
    57  {
    58  printf("Success to close input file\n");
    59  }
    60
    61 writeheader(&header,fp2);
    62
    63 printf("Can we get here?\n");
    64
    65
    66  if(ferror(fp2)) {
    67        printf("File2 Error\n");
    68        exit(1);
    69                  }
    70  if ( fclose( fp2 ) == 0 )
    71 { printf("Success to close output file\n");
    72 }
    73 return(0);
    74 }
    75
    76
    77
    78
    79 void readheader(HEADER *header,FILE *fp1)
    80 {
    81 printf("Here is the readheader function\n");
    82 fread(&(header->num1),sizeof(int),1,fp1);
    83 fread(&(header->num2),sizeof(header->num2),1,fp1);
    84 fread(&(header->num3),sizeof(int),1,fp1);
    85 fread(&(header->num4),sizeof(int),1,fp1);
    86 }
    87
    88 short**** construct_4D(int dimension1, int dimension2, int dimension3, int dimension4){
    89    short**** result;
    90    int i1, i2, i3;
    91    result = (short****)malloc(sizeof(short***)*dimension1);
    92    for (i1 = 0; i1 < dimension1; i1++){
    93        result[i1] = (short***)malloc(sizeof(short**)*dimension2);
    94        for (i2 = 0; i2 < dimension2; i2++){
    95            result[i1][i2] = (short**)malloc(sizeof(short*)*dimension3);
    96            for (i3 = 0; i3 < dimension3; i3++){
    97                result[i1][i2][i3] = (short*)malloc(sizeof(short)*dimension4);
    98            }
    99        }
    100    }
    101    return result;
    102 }

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Do the fopen-s succeed? You never check.

yes , fopen works

So explain not working. What happens? Crash? Bad results?
The bad thing occurs at line 51?
Also, this code is bad, if not altogether wrong:

datatable[i][j] = (short **)construct_4D(2,2,3,4);

You are allocating a 4D-array, yet truncating it to a 2D-array.

1. remove all those casts of malloc, see the FAQ.

> datatable[i][j] = (short **)construct_4D(2,2,3,4);
What???
You've already built a 4-D array, why are you doing it again?

> fread(&datatable[i][j][0][0],sizeof(short),6,fp1);
1. This assumes that the two inner dimensions are contiguous - they aren't.
Only the innermost array is contiguous.
2. Where did 6 come from?

I mean, from construct_4D(2,2,3,4); you use 2 and 4 (boogle) in the controlling for loop, so I suppose 6 comes from the remaining 2 and 3.

Basically, the array you're reading into is completely the wrong shape.