Traversing /boot/grub/grub.conf

[whatis]

Hi

I want to write a command, that will output the default "title" entry from the grub.conf file.

eg: cat /boot/grub/grub.conf | grep title

title Red Hat Enterprise Linux Server (2.6.18-128.1.6.el5)
title Red Hat Enterprise Linux Server (2.6.18-128.el5)

Now supposing the default=1 is set in the file, so I want the output "only" to be the second line.

Plz help with the pipelined command.

[whatis]

I already have the value of the 'default'
COUNT=`cat $ /boot/grub/grub.conf | grep default | awk 'BEGIN{FS="="};{print $2}'`

But I dont know how I can use this COUNT to get the corresponding 'title'. I tried using head/tail, but cudnt arrive at a consistent logic which will work for all 'default' values.

There are multiple enteries in my grub.conf file.

Plz suggest.

[Lakshmipathi]

Once you got the COUNT value you could try this.

grep 'title' /boot/grub/menu.lst | head -$COUNT | tail -1

[whatis]

Thanks Alot

But I believe, b'coz the default value starts with 0, it should be 'count+1' in the above statement.

[Lakshmipathi]

Thanks Alot

But I believe, b'coz the default value starts with 0, it should be 'count+1' in the above statement.

yes.you are right. Increment the count value.
Also note different distros will have their own format below is an example of my (Ubuntu 9.04
- the Jaunty Jackalope)menu.lst file
- you need to determine the correct "default" entry and it's value.

# menu.lst - See: grub(8), info grub, update-grub(8)
#            grub-install(8), grub-floppy(8),
#            grub-md5-crypt, /usr/share/doc/grub
#            and /usr/share/doc/grub-doc/.

## default num
# Set the default entry to the entry number NUM. Numbering starts from 0, and
# the entry number 0 is the default if the command is not used.
#
# You can specify 'saved' instead of a number. In this case, the default entry
# is the entry saved with the command 'savedefault'.
# WARNING: If you are using dmraid do not use 'savedefault' or your
# array will desync and will not let you boot your system.
default		0

## timeout sec
# Set a timeout, in SEC seconds, before automatically booting the default entry
# (normally the first entry defined).
timeout		3

## hiddenmenu
# Hides the menu by default (press ESC to see the menu)
hiddenmenu

# Pretty colours
#color cyan/blue white/blue

## password ['--md5'] passwd
# If used in the first section of a menu file, disable all interactive editing
# control (menu entry editor and command-line)  and entries protected by the
# command 'lock'
# e.g. password topsecret
#      password --md5 $1$gLhU0/$aW78kHK1QfV3P2b2znUoe/
# password topsecret

#
# examples
#
# title		Windows 95/98/NT/2000
# root		(hd0,0)
# makeactive
# chainloader	+1
#
# title		Linux
# root		(hd0,1)
# kernel	/vmlinuz root=/dev/hda2 ro
#

#
# Put static boot stanzas before and/or after AUTOMAGIC KERNEL LIST

### BEGIN AUTOMAGIC KERNELS LIST
## lines between the AUTOMAGIC KERNELS LIST markers will be modified
## by the debian update-grub script except for the default options below

## DO NOT UNCOMMENT THEM, Just edit them to your needs

## ## Start Default Options ##
## default kernel options
## default kernel options for automagic boot options
## If you want special options for specific kernels use kopt_x_y_z
## where x.y.z is kernel version. Minor versions can be omitted.
## e.g. kopt=root=/dev/hda1 ro
##      kopt_2_6_8=root=/dev/hdc1 ro
##      kopt_2_6_8_2_686=root=/dev/hdc2 ro
# kopt=root=UUID=5fc1d44d-7d5e-48f8-8c49-ddfd673d9c39 ro

## default grub root device
## e.g. groot=(hd0,0)
# groot=5fc1d44d-7d5e-48f8-8c49-ddfd673d9c39

## should update-grub create alternative automagic boot options
## e.g. alternative=true
##      alternative=false
# alternative=true

## should update-grub lock alternative automagic boot options
## e.g. lockalternative=true
##      lockalternative=false
# lockalternative=false

## additional options to use with the default boot option, but not with the
## alternatives
## e.g. defoptions=vga=791 resume=/dev/hda5
# defoptions=quiet splash

## should update-grub lock old automagic boot options
## e.g. lockold=false
##      lockold=true
# lockold=false

## Xen hypervisor options to use with the default Xen boot option
# xenhopt=

## Xen Linux kernel options to use with the default Xen boot option
# xenkopt=console=tty0

## altoption boot targets option
## multiple altoptions lines are allowed
## e.g. altoptions=(extra menu suffix) extra boot options
##      altoptions=(recovery) single
# altoptions=(recovery mode) single

## controls how many kernels should be put into the menu.lst
## only counts the first occurence of a kernel, not the
## alternative kernel options
## e.g. howmany=all
##      howmany=7
# howmany=all

## specify if running in Xen domU or have grub detect automatically
## update-grub will ignore non-xen kernels when running in domU and vice versa
## e.g. indomU=detect
##      indomU=true
##      indomU=false
# indomU=detect

## should update-grub create memtest86 boot option
## e.g. memtest86=true
##      memtest86=false
# memtest86=true

## should update-grub adjust the value of the default booted system
## can be true or false
# updatedefaultentry=false

## should update-grub add savedefault to the default options
## can be true or false
# savedefault=false

## ## End Default Options ##

title		Ubuntu 9.04, kernel 2.6.28-11-generic
uuid		5fc1d44d-7d5e-48f8-8c49-ddfd673d9c39
kernel		/boot/vmlinuz-2.6.28-11-generic root=UUID=5fc1d44d-7d5e-48f8-8c49-ddfd673d9c39 ro quiet splash 
initrd		/boot/initrd.img-2.6.28-11-generic
quiet

title		Ubuntu 9.04, kernel 2.6.28-11-generic (recovery mode)
uuid		5fc1d44d-7d5e-48f8-8c49-ddfd673d9c39
kernel		/boot/vmlinuz-2.6.28-11-generic root=UUID=5fc1d44d-7d5e-48f8-8c49-ddfd673d9c39 ro  single
initrd		/boot/initrd.img-2.6.28-11-generic

title		Ubuntu 9.04, memtest86+
uuid		5fc1d44d-7d5e-48f8-8c49-ddfd673d9c39
kernel		/boot/memtest86+.bin
quiet

### END DEBIAN AUTOMAGIC KERNELS LIST