Archive for the ‘Linux’ Category

Linux Kernel 3.0.0-rc1 Released

Linux creator, Linus Torvalds has released the 3.0.0-RC1 version of Linux kernel to mark the 20 years of Tux powered computing. Linus first released the 2.0 version of the Kernel about 15 years ago. The new release is surely going to make all Linux hackers and UNIX enthusiasts happy.

The 3.0 version adds support to Microsoft Kinnect – the gaming platform. Linus mentions in this email that the new Kernel code has been optimized for AMD Fusion and Intel Ivy & Sandy Bridge silicon. As expected, it also offers updated graphics drivers and some support for new hardware. The new Kernel is still in evolutionary stage and the new version was introduce to mark the beginning of the third decade. The OS has not been overhauled yet. There is lot of work that needs to be done and the RC needs some more refinement before its gold release.

You may read Linus Torvald’s mail to the newsgroup here.

Visit the Kernel archive.

Categories: Linux



WinSCP is freeware SCP (Secure Copy) client using SSH (Secure Shell). Its main purpose is safe copying files between local and remote computer. Beyond this basic function, it manages some other actions with files. It can do all basic operations with files, such as copying and moving. It also allows you to rename files and folders, create new folders, change properties of files and folders. One of two selectable program interfaces allows user to manage files even on local computer. Most operations can be done recursively for files in folders. WinSCP is also available as a plugin to two file managers, FAR and Servant Salamander.


  • Integration with Windows (drag&drop, URL, shortcut icons)
  • All common operations with files
  • Support for SFTP and SCP protocols over SSH-1 and SSH-2
  • Batch file scripting and command-line interface
  • Directory synchronization in several semi or fully automatic ways
  • Integrated text editor
  • Support for SSH password, keyboard-interactive, public key and Kerberos (GSS) authentication
  • Integrates with Pageant (PuTTY authentication agent) for full support of public key authentication
  • Windows Explorer-like and Norton Commander-like interfaces.
  • Optionally stores session information.
  • Optionally supports standalone operation using a configuration file in place of registry entries, suitable for operation from removable media
  • Translated into several languages
  • Graphical user interface

OS: Windows All

Licence: Open Source GPL



Download (Portable version):

LiLi USB Creator

LiLi USB Creator

LiLi USB Creator is a free software for Windows that allows you to create a bootable Live USB key with a Linux on it.

This software also offers an exclusive option of automatic virtualization to directly run Linux in Windows without any configuration nor installation.

  • create bootable Live USB of Ubuntu, Fedora, Debian, OpenSUSE, ArchLinux, Damn Small Linux, Puppy Linux and many others!
  • enable persistency of your data (available only on some Linux)
  • launch Linux directly in Windows with a special Portable VirtualBox
  • hide created files on the key
  • Available in: French, English, German, Italian, Spanish, Japanese, Norwegian, Swedish,Portuguese, Korean, Russian, Dutch and Hungarian

Anybody can use LiLi USB Creator. It’s really easy to use and you don’t have to be a computer geek !

Use the link below to follow a step by step procedure on how to use LiLi

OS: Windows 2000/XP/2003/Vista/7

License: Freeware



Categories: Free and Freeware, Linux

Areca Backup

Areca Backup

Areca Backup is a file backup tool written in java. It supports data compression & encryption, incremental backup, file history explorer and many other features. Areca Backup also includes a transaction mechanism which guarantees your backups´ integrity. As an additional security mesure areca also features a backup simulation module.
Backup Engine Features :

  • Archives compression (Zip & Zip64 format)
  • Archives encryption (AES128 & AES256 encryption algorithms)
  • Storage on local hard drive, network drive, USB key, FTP / FTPs server (with implicit and explicit SSL / TLS)
  • Source file filters (by extension, subdirectory, regular expression, size, date, status, with AND/OR operators)
  • Incremental, differential and full backup support
  • Archives merges / deletion: You can merge contiguous archives in one single archive or safely delete your latest archives.
  • As of date recovery: Areca allows you to recover your archives (or single files) as of a specific date.
  • Transaction mechanism: All critical processes (such as backups or merges) support a transaction mechanism (with commit / rollback management) which guarantees your backups’ integrity.
  • Backup reports: Areca generates backup reports that can be stored on your disk or sent by email.
  • Post backup scripts: Areca can launch shell scripts after backup.
  • Files permissions and symbolic links backup. (Linux only)
  • Support for delta backup (store only the modified parts of the files – not the whole files)

Graphical User Interface :

  • Archives content explorer. (including a ‘find file in archives’ feature)
  • Archive description: A manifest is associated to each archive, which contains various informations such as author, title, date, description, and some technical data.
  • File history explorer: Areca keeps track of your file’s history (creation / modifications / deletion) over your archives.
  • Backup simulation: useful to check wether a backup is necessary
  • User’s actions history: Areca keeps an history of all user’s actions (archives deletion, merges, backups, recoveries).

OS: Windows 2000/XP/2003/Vista/7

License: Open Source (GPL) v2



How to crypt/decrypt a file with vi?


Open the file using vi, type “:X“, enter the key (this key will be the password to see the crypted file) and then save and exit by “:wq“.

The file will be crypted.

You can use:

vi -x yourfile

to do the same thing.



To decrypt just the way you encrypted the file.

Open the file using vi, type “:X“, enter the key and after that the file will be visible and writable. If you close and save your file by “:wq” the file will be still crypted.


To descript forever the crypted file

Open the file using vi, type “:X“, push two times the “enter” button and then save and exit by “:wq“.

The file will be decrypted

Categories: Linux, Unix

SUID [Set User ID] – SGID – [Set Group ID]

SUID – [Set User ID]

SUID bit is set for files (mainly for scripts).
The SUID permission makes a script to run as the user who is the owner of the script, rather than the user who started it.

If “xarabas” is the owner of the script and “mandrake” tries to run the same script, the script runs with the ownership of “xarabas“.
If the root user wants to give permissions for some scripts to run by different users, he can set the SUID bit for that particular script.
So if any user on the system starts that script, it will run under the root ownership.

root user much be very carefull with this.


SGID – [ Set Group ID ]

If a file is SGID, it will run with the privileges of the files group owner, instead of the privileges of the person running the program.
This permission set also can make a similar impact. Here the script runs under the groups ownership.

You can also set SGID for directories.
Consider you have given 2777 permission for a directory.
Any files created by any users under this directory will come as follows.

-rw-rw-r– 1 mandrake LP1 0 Jun 11 17:30 1.txt

In the above example you can see that the owner of the file 1.txt is “mandrake” and the group owner is “LP1“.
So both “mandrake” and “LP1” will have access to the file 1.txt.

Now lets make this more intresting and complicated.
Create a directory “test“. Chmod it to 2777. Add sticky bit to it.

mkdir test
chmod 2777 test
chmod +t test

ls -al test
drwxrwsrwt 2 xarabas LP1 4096 Jun 13 2008 test

From the above permission set you can understand that SGID and sticky bit is set for the folder “test”.
Now any user can create files under the test directory.

drwxrwsrwt 2 xarabas LP1 4096 Jun 13 2008 .
-rw-rw-r– 1 mandrake LP1 0 Jun 11 17:30 1.txt
-rw-rw-r– 1 batman LP1 0 Jun 11 17:30 2.txt
-rw-rw-r– 1 joker LP1 0 Jun 11 17:30 3.txt

So all the “xarabas” user has access to all the files under the test directory.
He can edit, rename or remove the file.
mandrake” user has access to 1.txt only, “batman” has access to 2.txt only…

If sticky bit was not set for the test directory, any user can delete any files from the test directory, since the test directory has 777 permissions.
But now it not possible.

If “joker” tries to remove 1.txt
rm -f 1.txt
rm: cannot remove ‘1.txt’: Operation not permitted

Categories: Linux, Unix

Sticky bit

Sticky bit

The most common use of the sticky bit today is on directories.
When the sticky bit is set, only the item’s owner, the directory’s owner, or the superuser can rename or delete files. Without the sticky bit set, any user with write and execute permissions for the directory can rename or delete contained files, regardless of owner.
Typically this is set on the /tmp directory to prevent ordinary users from deleting or moving other users’ files

Consider you have a directory “/test“.
The chmod it to “777“, this command gives permissions for all the users to read, write and execute.
If you run chmod +t /test and now the /test directory content is the following:

Example: ls -al /test
drwxrwxrwt 2 xarabas LP1 4096 Jun 13 2008 .
-rw-rw-r– 1 xarabas LP1 0 Jun 11 17:30 1.txt
-rw-rw-r– 1 mandrake LP2 0 Jun 11 22:52 2.txt

From the above example “xarabas” is the owner of the test directory (see the first row). “xarabas” can delete or rename the files 1.txt and 2.txt. “mandrake” can delete or rename the file 2.txt only.

Concluding, if the sticky bit is set for a /test directory, only the owner of that directory or the owner of a file can delete or rename a file within that directory.

Categories: Linux, Unix
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