Friday, November 22, 2013

CHNTPW (Change Windows Password from Linux)

​This  chntpw is a tool to access windows registry from linux. This can edit windows login accounts and their passwords. This can also be used to edit the registry similar to regedit. First install this tool in your linux and follow the steps given below.

1. ”cd  /media/.../Windows/System32/config“
​    "/usr/sbin/chntpw -l SAM"
    This will print all user accounts in the windows system.

2. "chntpw  -u  Administrator sam"
     This will open interactive session to edit the user account Administrator.

3. "chntpw  -l  software"
     This will open interactive session to edit the registry software.
     For available commands in the interactive session type "?".

Control Flow Loops in Python

For Loop to reassign items in a list:

>>> s = [1,2,3]
​>>> for n in range(len(s)):
     s[n] = s[n]*2
>>> s
[2, 4, 6]

Call Python Within Shell Script

Shell scripts are easier to write but they lack the features provided by a programming language like python. But instead python can be used within shell scripts. Here are two examples.

​1. To get the file name ‘File’ from the full path ‘Path’:
File=`python -c "print '$Path'.split('/')[-1]"`

2. To get the directory ‘Dir’ from the full path ‘Path’ of file ‘File’:
Dir=`python -c "print '$Path'.rstrip(str('$File'))"`

Python Unicode

#In Python 2.X
#To convert Unicode to character:
​>>> for x in range(0x6000,0x6020,1):
          print unichr(x),  
怀 态 怂 怃 怄 怅 怆 怇 怈 怉 怊 怋 怌 怍 怎 怏 怐 怑 怒 怓 怔 怕 怖 怗 怘 怙 怚 怛 怜 思 怞 怟

​#In Python 3.X:
#To convert Unicode to character:
>>> for x in range(0x6000,0x6020,1):
          print(chr(x),end=' ')
怀 态 怂 怃 怄 怅 怆 怇 怈 怉 怊 怋 怌 怍 怎 怏 怐 怑 怒 怓 怔 怕 怖 怗 怘 怙 怚 怛 怜 思 怞 怟

#To convert character to Unicode:
>>> hex(ord('怀'))
’0×6000′
>>> for n in ‘सत्यमेव जयते’:
          print(ord(n), end=',')
2360,2340,2381,2351,2350,2375,2357,32,2332,2351,2340,2375,

Python Regular Expressions

Python has a ‘re’ module to handle regular expressions. Here are some examples.
​>>> import re
#Example 1: To extract the contents within double quotes in a string
>>> s = 'customer name is "FirstName LastName"'
>>> re.findall('".*"',s)
​['"FirstName LastName"']               #The result is a list

​#Example 2: To extract the individual words from a combined word like ‘FirstName’
>>> s = 'FirstName'
>>> re.findall('[A-Z][a-z]+',s)
['First', 'Name']  #The result is a list.
>>> ''.join(re.findall('[A-Z][a-z]+',s))
'FirstName'      #To get the string from the list​

​#Example 3: To replace all numbers with a ‘.’ suffix’
>>> s = '1 one 11 eleven'
>>> re.sub("(\d)( )","\\1.\\2",s)
​'1. one 11. eleven'

Thursday, November 21, 2013

Github

GITHUB:

 To init github type the command followed by repository name (say TCP):
    git init TCP.git

 Then cd to this git directory
   cd TCP.git

 Then add the remote repository:
   git remote add origin https://github.com/user-name/TCP.git

 To get the files from the TCP.git repository:
   git pull origin master

 After Changing files, commit them:
   git add .
   git commit -a
   This will open a nano editor window.
   Remove comment in modified file lines and save the file by pressing escape and "Y".

 To update the repository:
   git push origin master
   This will ask for username and password.

 To check status:
   git status

SSH with no password

SSH with no password:
​Here is a two step process to use SSH/SCP and access remote machines without password.

1. Generate a public/private rsa key pair in the local machine (client):
Command:  ”ssh-keygen“
The public key will be saved in a file at ~/.ssh/id_rsa

2. Copy the id to the remote machine (server):
Command: “ssh-copy-id  UserName@ServerAddress“

Thats all need to do. Now you can try “ssh UserName@ServerAddress” and it should login without asking password. Same with scp command.

Android App Developer

I have developed and posted several apps in Google Play Store in different categories like Math, Education, Philosophy, Health etc . Please check them by visiting
Android app on Google Play
If you need a specific app for your business or personal reasons, please contact me and I may even develop it free for you, provided if I can show ads with the app.

Android has several advantages over other mobile OS. They are:
  • It is based on Linux which has inherent security and user permissions.
  • As it is free, it is used by several companies in their devices which brings the cost down.
  • It has huge potential to evolve as a standard OS that can be used in several embedded systems and devices.
  • It is developed and supported by Google.
  • It is open sourced and evolves faster than others.