Since MS‑DOS, I know system invocation using interrupts. In old papers, I saw reference to int 80h to invoke system functions on Linux. Since a rather long time now, I know int 80h is deprecated in favour of the syscall instruction. But I can't get it working on my 32 bits machine.
Is the syscall instruction to be used on 64 bits platform only?
I have just bought an hp pavilion DV6 ( intel i7 processor + 6G of RAM) running windows 7( 64 bits). I downloaded Ubuntu 12.04 64 bits and correctly burned it to a DVD. My problem starts when I try to boot the computer from DVD as a first step to install Ubuntu. In fact, the home page of Ubuntu is shown without further prompts ( no button of install of try it before install).
I'd like to ask, in what order are bits and bytes sent through the cable (what is the endianness of bits and bytes)? And does the network layer simply pass the formed package to the data link layer, or does it perform any transformations of bits/bytes?
This article states, that it's big endian for bytes and little endian for bits. Can you confirm that?
0000000000000000 - 00007fffffffffff (=47 bits) user space, different per mm
ffff800000000000 - ffff80ffffffffff (=40 bits) guard hole
ffff880000000000 - ffffc7ffffffffff (=64 TB) direct mapping of all phys.