uname -a

# Let's issue a uname -a command on 64-bit Linux
$ uname -a
Linux host 4.0.5-300.fc22.x86_64 #1 SMP Mon Jun 8 16:15:26 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux
# Let's launch a bash shell with an i386 architecture exposed to the process
$ setarch i386 bash
# Watch uname -a give us the exposed architecture, not the kernel architecture
$ uname -a
Linux host 4.0.5-300.fc22.x86_64 #1 SMP Mon Jun 8 16:15:26 UTC 2015 i686 i686 i386 GNU/Linux