title: How is linux simultaneously 32bit and 64bit? Or is that something handled in glibc?
body: <p>How is Linux simultaneously 32bit and 64bit? Or is that something handled in glibc?</p>
  
  <p>I run CentOS 5.3 and it is a "64 bit" version; although I build things for 64 bit and 32 bit. From what I think I know, Windows supposedly has a 32bit emulator. Does Linux do the same thing? Is it in userspace or kernel space?</p>
  
  <p>If libc handles it, is it kind of like a emulator that says, I'll link with 32 bit apps, but speak 64 bit to the kernel?</p>