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Comment a block in shell

Posted 08-31-2011 at 12:22 AM by hi2arun

Tags bash, script

We all know, to comment out a line in shell script, '#' token is inserted in the line that needs to be made dead.
Eg:

Code:

# This is a dead line
echo "This line is live"

However, '#' token can be pesky if a block of lines need to be commented out.
Say, to comment out the following block using '#'

Code:

# comment starts here
# All these lines
# are blocked
# using '#' token
# ...
# ...
# ...

...

hi2arun

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Mapping address to line - Linux

Posted 08-31-2011 at 12:20 AM by hi2arun

Tags debug, kernel, panic

Well.. when you write your own kernel module, in the devel stage, chances for bringin down the kernel (panic.. ah sick) are huge.
Oops (pet name for kernel panic) mostly spits lots of martian traces that include stack addresses, registers and its value, EIP, etc.

To know the culprit line that caused panic, decode the address to line as follows:
EIP wud luk like...

Code:

EIP: [] ip_check+0x45a/0x21a [ip_tables] SS:ESP 0049:c098281a

Look at the selection...

hi2arun

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How to see what is in an RPM without installing it?

Posted 08-31-2011 at 12:18 AM by hi2arun

Tags rpm, rpm commands

Datz simple!
1. Create a temp directory

Code:

# mkdir x

2. Change directory

Code:

# cd x

3. Now extract the RPM

Code:

# rpm2cpio /path/of/ur/RPM/file.rpm | cpio -dmi

There u go! Now you have ur RPM xtractd in directory 'x'

hi2arun

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"Wait until a process ends, a download ends, or a file conversion ends, then do X"

Posted 08-30-2011 at 03:06 PM by the dsc (linux-related notes)
Updated 08-30-2011 at 09:41 PM by the dsc (a small improvement)

Tags bash, helper scripts, tools, wait

Sometimes you want the computer to shut down after you've finished downloading something or converting some large file into some other format, but you want to go out or go to sleep instead of waiting and checking for it yourself.

For these situations I've come up with two tiny scripts. The first one waits until a file hasn't changed its size on three consecutive intervals of twenty seconds:

Code:

a=0 ; file="$1" ; if [ -f "$file.part" ] ; then file="$file.part"

...

the dsc

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Recovering Windows boot after deleting the Linux partitions

Posted 08-30-2011 at 02:32 PM by TobiSGD
Updated 08-30-2011 at 02:36 PM by TobiSGD

So you tried Linux in dual-boot with your Windows installation and after you deleted the Linux partition(s) your Windows won't boot anymore.
There is a simple fix for that, you have to just re-install your Windows boot-loader.

Windows XP:

Boot the system from your Windows XP-CD, just like you booted the Linux-CD/DVD before.
Start the recovery/repair console (not the repair installation).
Type
Code:
```
fixmbr.exe
```
and press Enter.
Reboot.

Windows Vista/7: