root [~]# uname -m i686 root [~]# perl -MPOSIX -le '@a=POSIX::uname(); print pop @a' x86_64 root [~]# root [~]# strace -e uname -vvFf -s 4096 uname -m uname({sysname="Linux", nodename="TRUNCATED", release="2.6.9-023stab033.1-smp", version="#1 SMP Mon Oct 23 21:43:16 MSD 2006", machine="x86_64"}) = 0 uname({sysname="Linux", nodename="TRUNCATED", release="2.6.9-023stab033.1-smp", version="#1 SMP Mon Oct 23 21:43:16 MSD 2006", machine="x86_64"}) = 0 Process 5784 attached [pid 5784] uname({sysname="Linux", nodename="TRUNCATED", release="2.6.9-023stab033.1-smp", version="#1 SMP Mon Oct 23 21:43:16 MSD 2006", machine="x86_64"}) = 0 Process 5784 detached --- SIGCHLD (Child exited) @ 0 (0) --- i686 root [~]# strace -e uname -vvFf -s 4096 perl -MPOSIX -e 'POSIX::uname()' uname({sysname="Linux", nodename="TRUNCATED", release="2.6.9-023stab033.1-smp", version="#1 SMP Mon Oct 23 21:43:16 MSD 2006", machine="x86_64"}) = 0 uname({sysname="Linux", nodename="TRUNCATED", release="2.6.9-023stab033.1-smp", version="#1 SMP Mon Oct 23 21:43:16 MSD 2006", machine="x86_64"}) = 0 root [~]# root [~]# file /lib/ld-2.3.3.so /lib/ld-2.3.3.so: ELF 32-bit LSB shared object, Intel 80386, version 1 (SYSV), not stripped root [~]# root [~]# for i in $(ls /lib); do file $i; done | grep 64 root [~]# for i in $(ls /usr/lib); do file $i; done | grep 64 root [~]# root [/boot]# cat /boot/kernel.h | grep type /* Kernel type i686 */ root [/boot]#