Running .dat files in linux and using vlc

.dat files which are generally vedio files are played easily in windows media player, but in linux not all players support .dat files.

We can use one of the following methods to run a .dat file

1. using vlc
vlc by default throws error when we try to run a .dat file.

File reading failed: VLC could not read the file.

To run a .dat in a vedio cd file using vlc do the following

open vlc media-> open Disc Under Disc Selection : Select the SVCD/VCD Change Disc Device to /dev/sr0 or levae it blank click on play

The file in the cd should start playing automatically.

2. We can use the gxine player to run .dat file

$ sudo apt-get install gxine

Once the installation is done a new player called "gxine" will appear under sound and video menu which will directly play the .dat file with out any problems.

3. We can install windows media player using wine and run the .dat file from the windows media player.

du: Finding the file/folder size from command line in linux

To find the amount of space occupied by any file or folder in the system we can use the command du.

Let us say we have a folder test which contains the files file1,file2,file3,temp

To find the size of the folder test

$ du test 4 test/temp 8 test

The first column Indicates the size of the folder and the second column gives the name of the folder. By default du also lists the sizes of only the sub folders and not of files.
In case we want to have a look at the size of the files too we can use the option "-a"

$ du -a test 0 test/file2 0 test/file3 0 test/file1 4 test/temp 8 test

The size column if displayed with no suffix can be difficult to read for bigger sized files, to make the reading easier we can use the option "-h" which sill convert it into more human readable form

$ du -h test 4.0K test/temp 8.0K test

The suffix K indicating the size is in Kilo bytes. For Mega bytes it will be M for giga G etc.
If we just want the size of the folder and not its sub folders we can use the option "-s"

$ du -s test 8.0K test

We can also pass file names to find the size of a file instead of a folder.

$ du -h test/file1 0 test/file1

Thus we can easily find the space occupied by any file or folder on the system using the du command

Different ways to find the linux kernel version

Here are two ways to find out the currently running kernel version of linux

1. Using uname to find the linux kernel version

$ uname -r 3.2.1

2. Using sysctl to find the linux kernel version

$ sysctl kernel.osrelease kernel.osrelease = 3.2.1

3. Using proc entry to find the linux kernel version

$ cat cat /proc/sys/kernel/osrelease 3.2.1

No manual entry for pthread_create

While learning pthreads, if you try to have look at the man pages of pthread and get the error

$ man pthread_create No manual entry for pthread_create

Then you need to install the package manpages-posix-dev. If you are running debian based systems you can run the command.

$ sudo apt-get install manpages-posix-dev

Once the package is installed you should be able see the man pages for all posix related functions.

Finding the filesystem type of a partition in linux

To find the type of filesystem a partition or a media is of we can use the commands "df" or "mount".

Using df

$ df -T Filesystem Type 1K-blocks Used Available Use% Mounted on /dev/sda1 ext4 53067292 47601336 2770228 95% / tmpfs tmpfs 127140 0 127140 0% /lib/init/rw udev tmpfs 121484 220 121264 1% /dev tmpfs tmpfs 127140 4 127136 1% /dev/shm

The column with the heading "Type" gives the filesystem type. So the partition /dev/sda1 is of type ext4

To find the filesystem type of a specific partition pass the partition as the argument.

$ df -T /dev/sda1 Filesystem Type 1K-blocks Used Available Use% Mounted on /dev/sda1 ext4 53067292 47601332 2770232 95% /

Using mount

$ mount /dev/sda1 on / type ext4 (rw,errors=remount-ro) tmpfs on /lib/init/rw type tmpfs (rw,nosuid,mode=0755) proc on /proc type proc (rw,noexec,nosuid,nodev) sysfs on /sys type sysfs (rw,noexec,nosuid,nodev) udev on /dev type tmpfs (rw,mode=0755) tmpfs on /dev/shm type tmpfs (rw,nosuid,nodev) devpts on /dev/pts type devpts (rw,noexec,nosuid,gid=5,mode=620) fusectl on /sys/fs/fuse/connections type fusectl (rw) binfmt_misc on /proc/sys/fs/binfmt_misc type binfmt_misc (rw,noexec,nosuid,nodev) none on /proc/fs/vmblock/mountPoint type vmblock (rw)

As listed the partition /dev/sda1 is of type ext4.
We can find the specific partition type by combining mount with grep.

$ mount | grep /dev/sda1 /dev/sda1 on / type ext4 (rw,errors=remount-ro)