Thread: big endian-small endian problem

I m getting 37376 instead of 146 for width and 27393 instead of 363 for height. I guess big endian-small endian problem has occured. plz help me to solve this problem.

Code:

#include <stdio.h>
#include <stdlib.h>


typedef struct {
        char type[3];
        char code[3];
        unsigned short int width;
        unsigned short int height;
        char flags;
        char bgColorI;
        char pARatio;
}__attribute__((packed)) HEADER;

int main(int argc,char **argv)
{
        FILE *fptr;
       HEADER header;

        if (argc < 2) {
                fprintf(stderr,"Usage: %s filename\n",argv[0]);
                exit(-1);
        }
        if ((fptr = fopen(argv[1],"r+b")) == NULL) {
                fprintf(stderr,"Unable to open GIF file \"%s\"\n",argv[1]);
                exit(-1);
        }
        fread(&header,sizeof(HEADER),1,fptr);
       printf("\n Width = %d , Height =%d\n", header.width,header.height);

I guess mine is also little endian, I m using Intel processor, I gues it wont work for big endian
is there any function which can solve this problem??(NUXI problem)

Well you have several options.

• You can make a function to reverse the order:
  
  Code:

  unsigned short reverse_short(unsigned short num)
  {
  	return (num << 8) | (num >> 8);
  }

• You can call one of the networking functions like ntohs() to do the same.
• You can read the file into a char buffer, and individually store each member of the struct.

The advantage of the last two options is that your code will work on any platform.