File Operations: Help with fwrite

[Rohit Arul Raj <rohitarulraj at gmail dot com>]

Hello All,

I need some clarification for fwrite.

#include<stdio.h>

int main()
{
?unsigned long writeBuffer [64];
?unsigned long Pos;
?unsigned long j;

?FILE* pFile = fopen("tmp.txt", "w+t");

?for(j = 0; j < 64; j++)
? ?writeBuffer[j] = 2560 + j * 4; ? ? ? ? ? ? // -----------------------(A)

?fwrite(writeBuffer, 1, 256, pFile);

?fgetpos(pFile, &Pos);
?printf("pos = %d\n", Pos);

?fclose (pfile);
}

-------------------------------------------
Expected output : 256
Actual Output ? ?: ?320
---------------------------------------------

1) Can i use fwrite even though the file has been opened in text mode?
? ?If yes, then will using fwrite change the file mode to binary?

2) i do get the expected output for all the below mentioned cases:
? ?a) open the file in binary mode.
? ?b) Change 2560 to 0 in statement [A].
? ?c) Write an unsigned char instead of an unsigned int.

I understand that the way data's get stored using fprintf and fwrite
are different. But still if i use fwrite and dump 256 bytes of data in
to a file, fgetpos should have returned 256?

Any one can help me with this?

Thanks,
Rohit