were to find initdefault runlevel in linux min15 i mean in which file?

Actually i found initdefault value in the file /etc/inittab in redhat linux as below....but iam unble to find same file in linx mint15 .....kindly help me were can i see the same kind of file...

in Redhat linux:
================>

[root@localhost ~]# cat /etc/inittab
# inittab is only used by upstart for the default runlevel.
#
# ADDING OTHER CONFIGURATION HERE WILL HAVE NO EFFECT ON YOUR SYSTEM.
#
# System initialization is started by /etc/init/rcS.conf
#
# Individual runlevels are started by /etc/init/rc.conf
#
# Ctrl-Alt-Delete is handled by /etc/init/control-alt-delete.conf
#
# Terminal gettys are handled by /etc/init/tty.conf and /etc/init/serial.conf,
# with configuration in /etc/sysconfig/init.
#
# For information on how to write upstart event handlers, or how
# upstart works, see init(5), init(8), and initctl(8).
#
# Default runlevel. The runlevels used are:
#   0 - halt (Do NOT set initdefault to this)
#   1 - Single user mode
#   2 - Multiuser, without NFS (The same as 3, if you do not have networking)
#   3 - Full multiuser mode
#   4 - unused
#   5 - X11
#   6 - reboot (Do NOT set initdefault to this)
#
id:5:initdefault:


In Linux Mint 15:
==============>

bharath-virtual-machine ~ # cat /etc/inittab
cat: /etc/inittab: No such file or directory
bharath-virtual-machine ~ #




And also once kernel starts the init process it checks for the file /etc/rc.d/rc.sysinit in redhat linux as below.....
IN REDHAT
=============>
[root@localhost rc.d]# ls -l /etc/rc.d/rc.sysinit
-rwxr-xr-x. 1 root root 19114 May 23  2012 /etc/rc.d/rc.sysinit
[root@localhost rc.d]#

[root@localhost etc]# ls -ld */ | grep -i "rcc*"
drwxr-xr-x.  2 root root 4096 Jul  4 11:37 rc0.d/
drwxr-xr-x.  2 root root 4096 Jul  4 11:37 rc1.d/
drwxr-xr-x.  2 root root 4096 Jul  4 11:37 rc2.d/
drwxr-xr-x.  2 root root 4096 Jul  4 11:37 rc3.d/
drwxr-xr-x.  2 root root 4096 Jul  4 11:37 rc4.d/
drwxr-xr-x.  2 root root 4096 Jul  4 11:37 rc5.d/
drwxr-xr-x.  2 root root 4096 Jul  4 11:37 rc6.d/
drwxr-xr-x. 10 root root 4096 Jul  8 11:49 rc.d/
[root@localhost etc]#

But iam unable to find same file in linux mint instead i found as below rc directories....

IN LINUX MINT15
===============>

bharath-virtual-machine etc # ls -ld */ | grep -i "rcc*"
drwxr-xr-x 2 root    root     4096 Jun 29 08:02 rc0.d/
drwxr-xr-x 2 root    root     4096 Apr 26 00:01 rc1.d/
drwxr-xr-x 2 root    root     4096 Apr 26 00:01 rc2.d/
drwxr-xr-x 2 root    root     4096 Apr 26 00:01 rc3.d/
drwxr-xr-x 2 root    root     4096 Apr 26 00:01 rc4.d/
drwxr-xr-x 2 root    root     4096 Apr 26 00:01 rc5.d/
drwxr-xr-x 2 root    root     4096 Jun 29 08:02 rc6.d/
drwxr-xr-x 2 root    root     4096 Jun 10 16:08 rcS.d/
bharath-virtual-machine etc #