Hi Javier,
>I'm a bit confused, why is using 12 bytes if it's a char + 2 int's?
Probably (and I say that because I am making a presumption) because your system requires/recommends the int data types to be aligned on a 4 byte boundary.
So the compiler puts in padding bytes between the char and the int so that the structure will comply with your architecture's restrictions/recommendations.
Your print loop is displaying the pad bytes, which will contain uninitialized random data.
HTH,
--Eljay
PS: You may want to change your code to printf("%02x ", buffer[a] & 0xFF); to avoid undesirable sign extension and make the code 8-bit platform agnostic regardless whether char is signed or unsigned under the covers.
