knoppix@Knoppix:~$ mount
/dev/root on / type ext2 (rw)
/ramdisk on /ramdisk type tmpfs (rw,size=411856k,mode=755)
/UNIONFS on /UNIONFS type aufs (rw,br:/ramdisk:/KNOPPIX)
/dev/sda3 on /cdrom type vfat (ro,nodev,fmask=0022,dmask=0022,codepage=cp437,ioc harset=iso8859-1)
/dev/cloop on /KNOPPIX type iso9660 (ro)
/proc/bus/usb on /proc/bus/usb type usbfs (rw,devmode=0666)
/dev/pts on /dev/pts type devpts (rw)
/dev/sda3 on /media/sda3 type vfat (rw,nosuid,nodev,umask=000,shortname=winnt,uid=100 0,gid=1000)
/media/sda3/knoppix.img on /KNOPPIX.IMG type ext2 (rw,loop=/dev/loop0)
persistent on /UNIONFS type aufs (rw,br:/KNOPPIX.IMG:/KNOPPIX)
knoppix@Knoppix:~$ cat /proc/mounts
rootfs / rootfs rw 0 0
/dev/root.old / ext2 rw 0 0
/proc /proc proc rw 0 0
/sys /sys sysfs rw 0 0
/dev/sda3 /cdrom vfat rw,nodev,fmask=0022,dmask=0022,codepage=cp437,ioch arset=iso8859-1 0 0
/dev/cloop /KNOPPIX iso9660 ro 0 0
/ramdisk /ramdisk tmpfs rw 0 0
/UNIONFS /UNIONFS aufs rw,xino=/ramdisk/.aufs.xino,br:/ramdisk=rw:/KNOPPIX=ro 0 0
/proc/bus/usb /proc/bus/usb usbfs rw 0 0
/dev/root.old /dev/.static/dev ext2 rw 0 0
tmpfs /dev tmpfs rw 0 0
/dev/sda3 /media/sda3 vfat rw,nosuid,nodev,fmask=0022,dmask=0022,codepage=cp4 37,iocharset=iso8859-1 0 0
/dev/loop0 /KNOPPIX.IMG ext2 rw 0 0
persistent /UNIONFS aufs rw,xino=/KNOPPIX.IMG/.aufs.xino,br:/KNOPPIX.IMG=rw:/KNOPPIX=ro 0 0
/dev/pts /dev/pts devpts rw 0 0
knoppix@Knoppix:~$ ls /UNIONFS/usr/include # this produces the same as ls /usr/include
SDL bfdlink.h diet dmraid kino pci t.h
X11 capi20.h dis-asm.h gettext-po.h libcryptsetup.h python2.3 xchat
ansidecl.h capicmd.h dlg_colors.h initreq.h libiberty.h python2.4
autosprintf.h capiutils.h dlg_config.h isdn_dwabclib.h ntfs-3g qobex
bfd.h dialog.h dlg_keys.h kde openvpn symcat.h
knoppix@Knoppix:~$ ls /KNOPPIX/usr/include # this is what I expect to see in /usr/include!!!!
SDL cursesf.h ftw.h math.h protocols syscall.h
X11 cursesm.h gconv.h mcheck.h pthread.h sysexits.h
_G_config.h cursesp.h getopt.h memory.h pty.h syslog.h
a.out.h cursesw.h gettext-po.h menu.h pwd.h tar.h
aio.h cursslk.h glob.h mntent.h python2.3 term.h
aliases.h dialog.h gnu monetary.h python2.4 termcap.h
alloca.h diet gnu-versions.h mqueue.h qobex termio.h
ansidecl.h dirent.h grp.h ncurses.h re_comp.h termios.h
ar.h dis-asm.h iconv.h ncurses_dll.h regex.h tgmath.h
argp.h dlfcn.h ieee754.h net regexp.h thread_db.h
argz.h dlg_colors.h ifaddrs.h netash resolv.h time.h
arpa dlg_config.h initreq.h netatalk rpc ttyent.h
asm dlg_keys.h inttypes.h netax25 rpcsvc ucontext.h
asm-generic dmraid isdn_dwabclib.h netdb.h sched.h ulimit.h
asm-i486 elf.h jconfig.h neteconet scsi unctrl.h
asm-x86_64 endian.h jerror.h netinet search.h unistd.h
assert.h envz.h jmorecfg.h netipx semaphore.h ustat.h
autosprintf.h err.h jpegint.h netpacket setjmp.h utime.h
bfd.h errno.h jpeglib.h netrom sgtty.h utmp.h
bfdlink.h error.h kde netrose shadow.h utmpx.h
bits eti.h langinfo.h nfs signal.h values.h
byteswap.h etip.h lastlog.h nl_types.h spawn.h wait.h
c++ execinfo.h libcryptsetup.h nptl stab.h wchar.h
capi20.h fcntl.h libgen.h nss.h stdint.h wctype.h
capicmd.h features.h libiberty.h ntfs-3g stdio.h wordexp.h
capiutils.h fenv.h libintl.h obstack.h stdio_ext.h xchat
complex.h fmtmsg.h libio.h openvpn stdlib.h xlocale.h
cpio.h fnmatch.h limits.h panel.h string.h zconf.h
crypt.h form.h link.h paths.h strings.h zlib.h
ctype.h fpu_control.h linux pci stropts.h
curses.h fstab.h locale.h poll.h symcat.h
cursesapp.h fts.h malloc.h printf.h sys