Hi, On Jan 23, 2008 10:18 AM, Li Xiaodong <lixd@xxxxxxxxxxxxxx> wrote: > > Thank you. > Actually, I do not know what is little-endian and what is big-endian before > this time. > Despite that mistake, are the arrangements of memory I wrote correct (on > little-endian processor)? Here is a clear explanation: http://en.wikipedia.org/wiki/Endianness#Examples_of_storing_the_value_0x0A0B0C0D_in_memory Q1 was correct: 0 34 1 ef 2 cd on little endian and 0 cd 1 ef 2 34 on big endian. Q2: since the offsets were defined as offset 0 i/o address offset 3 i/o value The i/o address is 0xef4523 on little endian, and 0x2345ef on big endian. The i/o value is 0x0102df on little endian, and 0xdf0201 on little endian It's true that the offsets look strange, since normally one would have 4 bytes for such values (32-bit addresses). Q3: correct. The value you write in C is always with MSB first, and LSB last. During compilation, this is translated to the correct byte order for the machine you are targeting. Best regards, Thomas > > > > -----Original Message----- > > From: Thomas De Schampheleire [mailto:patrickdepinguin@xxxxxxxxx] > > Sent: Wednesday, January 23, 2008 5:10 PM > > To: Li Xiaodong > > Cc: vichy.kuo@xxxxxxxxx; kernelnewbies@xxxxxxxxxxxx > > Subject: Re: Question about Endian Order > > > > Hello, > > > > On Jan 23, 2008 9:37 AM, Li Xiaodong <lixd@xxxxxxxxxxxxxx> wrote: > > > Hi Vichy, > > > > > > To q1, > > > > > > I think the memory contents should be (on Linux): > > > > I think you are mistaken here. The endianness is not a property of the > > operating system, but rather a property of the processor you are > > running on. Linux runs both on little endian (like x86) as on big > > endian processors. Some processors can even run as little endian and > > as big endian, where you can choose which one you want by executing a > > certain instruction or writing to a certain register. > > > > Thomas > > > > -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx Please read the FAQ at http://kernelnewbies.org/FAQ
