fundamentals of programming languages

Tuesday, August 5, 2014

Introduction To Open Source Operating System -

Open Source –

Open source is a type of license, that allows users access the source code (of a software or operating system) to view, modify and again redistribute .

There are various open source operating systems and open source software available. They are freely available to users to use, modify and re-distribute.

Open Source Operating Systems Are –

UNIX,

LINUX,

ANDROID and so on.

Open Source Software Are –

Scilab (software)

Mozilla Firefox (web browser)

Eclipse (Integrated Development Environment).

Operating Systems –

Using operating system, you can use your computer system. Examples of operating systems are – Windows XP, Windows 7, Windows 8, UNIX, LINUX, SUN SOLARIS, APPLE MACINTOSH etc.

Open Source Operating Systems –

Are freely available to end users of a computer system. Users can download these operating system, install it on their PCs and use them, without paying a single rupee.

Users can view the source code of open source OS, can modify that or can add some extra code.

Examples of open source operating system are – UNIX, LINUX, BOSS (Bharat Operating System), Andriod and so on.

Flavours (Types) Of LINUX Operating System –

There are various types of linux operating system available in market. Like –

1. Redhat Linux

2. Fedora

3. Ubuntu

4. Mandrak

5. SUSE

6. Debian Knoppix.

Boss (Bharat Operating System) –

- Is an Indian version of open source operating system.

- It is based on Debian Flavour if LINUX.

- It is developed by C-DAC (Center for Development of Advanced Computing).

- It has user friendly GUI (Graphical User Interface).

- It contains Indian version of Open Office – BHARATHEEYA OPEN OFFICE.

- It has – 3D desktop.

- It contains - an application to send SMS – KENNEL.

Difference Between Open Source And Closed Source Operating System –

Open source OS	Closed Source OS
Ex. UNIX, LINUX, ANDROID	Ex. WINDOWS, MACINTOSH
Free	Need to be purchased
Difficult to use	Easy to use
More reliable	Less reliable
More Features	Less Features
More secure	Less Secure

Friday, May 30, 2014

BASIC UNIX COMMANDS

cal -This command will print a calendar for a specified month and/or year.

To show this month's calendar, enter:

cal
To show a twelve-month calendar for 2008, enter:

cal 2008

To show a calendar for just the month of June 1970, enter:

cal 6 1970

cat -This command outputs the contents of a text file. You can use it to read brief files or to concatenate files together.

To append file1 onto the end of file2, enter:

cat file1 >> file2

To view the contents of a file named myfile, enter:

cat myfile

Because cat displays text without pausing, its output may quickly scroll off your screen. Use the less command (described below) or an editor for reading longer text files.

cd -This command changes your current directory location. By default, your Unix login session begins in your home directory.

To switch to a subdirectory (of the current directory) named myfiles, enter:

cd myfiles

To switch to a directory named /home/dvader/empire_docs, enter:

cd /home/dvader/empire_docs

To move to the parent directory of the current directory, enter:

cd ..

To move to the root directory, enter:

cd /

To return to your home directory, enter:

cd

chmod -This command changes the permission information associated with a file.

Every file (including directories, which Unix treats as files) on a Unix system is stored with records indicating who has permission to read, write, or execute the file, abbreviated as r, w, and x.

These permissions are broken down for three categories of user: first, the owner of the file; second, a group with which both the user and the file may be associated; and third, all other users.

These categories are abbreviated as u for owner (or user), g for group, and o for other.

To allow yourself to execute a file that you own named myfile, enter:

chmod u+x myfile

To allow anyone who has access to the directory in which myfile is stored to read or execute myfile, enter:

chmod o+rx myfile

You can view the permission settings of a file using the ls command, described below.

Note: Be careful with the chmod command. If you tamper with the directory permissions of your home directory, for example, you could lock yourself out or allow others unrestricted access to your account and its contents.

For more, see In Unix, how do I change the permissions for a file?

cp -This command copies a file, preserving the original and creating an identical copy. If you already have a file with the new name, `cp` will overwrite and destroy the duplicate. For this reason, it's safest to always add `-i` after the `cp` command, to force the system to ask for your approval before it destroys any files.

The general syntax for `cp` is:

cp -i oldfile newfile
To copy a file named meeting1 in the directory /home/dvader/notes to your current directory, enter:

cp -i /home/dvader/notes/meeting1 .

The . (period) indicates the current directory as destination, and the -i ensures that if there is another file named meeting1 in the current directory, you will not overwrite it by accident.
To copy a file named oldfile in the current directory to the new name newfile in the mystuff subdirectory of your home directory, enter:

cp -i oldfile ~/mystuff/newfile

The ~ character (tilde) is interpreted as the path of your home directory.

Note: You must have permission to read a file in order to copy it.

date -The `date` command displays the current day, date, time, and year.

To see this information, enter:

date

df -This command reports file system disk usage (i.e., the amount of space taken up on mounted file systems).

For each mounted file system, `df` reports the file system device, the number of blocks used, the number of blocks available, and the directory where the file system is mounted.

To find out how much disk space is used on each file system, enter the following command:

df

If the df command is not configured to show blocks in kilobytes by default, you can issue the following command:

df -k

du -This command reports disk usage (i.e., the amount of space taken up by a group of files).

The `du` command descends all subdirectories from the directory in which you enter the command, reporting the size of their contents, and finally reporting a total size for all the files it finds.

To find out how much disk space your files take up, switch to your home directory with the cd command, and enter:

du

The numbers reported are the sizes of the files; on different systems, these sizes will be in units of either 512 byte blocks or kilobytes. To learn which is the case, use the man command, described below. On most systems, du -k will give sizes in kilobytes.

find -The `find` command lists all of the files within a directory and its subdirectories that match a set of conditions. This command is most commonly used to find all of the files that have a certain name.

To find all of the files named myfile.txt in your current directory and all of its subdirectories, enter:

find . -name myfile.txt -print

To look in your current directory and its subdirectories for all of the files that end in the extension .txt , enter:

find . -name "*.txt" -print

In these examples, the . (period) represents your current directory. It can be replaced by the full pathname of another directory to search. For instance, to search for files named myfile.txt in the directory /home/user/myusername and its subdirectories, enter:
find /home/user/myusername/ -name myfile.txt -print On some systems, omitting the final / (slash) after the directory name can cause find to fail to return any results.
As a shortcut for searching in your home directory, enter:

find "$HOME/" -name myfile.txt -print

jobs -This command reports any programs that you suspended and still have running or waiting in the background (if you had pressed `Ctrl-z` to suspend an editing session, for example).

For a list of suspended jobs, enter:

jobs

Each job will be listed with a number; to resume a job, enter % (percent sign) followed by the number of the job. To restart job number two, for example, enter:

%2

This command is only available in the csh, bash, tcsh, and ksh shells.

kill -Use this command as a last resort to destroy any jobs or programs that you suspended and are unable to restart. Use the jobs command to see a list of suspended jobs.

To kill suspended job number three, for example, enter:

kill %3
Now check the jobs command again. If the job has not been cancelled, harsher measures may be necessary. Enter:

kill -9 %3

less and more -Both `less` and `more` display the contents of a file one screen at a time, waiting for you to press the Spacebar between screens.

This lets you read text without it scrolling quickly off your screen. The `less` utility is generally more flexible and powerful than `more`, but `more` is available on all Unix systems while `less` may not be.

To read the contents of a file named textfile in the current directory, enter:

less textfile

The less utility is often used for reading the output of other commands. For example, to read the output of the ls command one screen at a time, enter:

ls -la | less

In both examples, you could substitute more for less with similar results. To exit either less or more, press q . To exit less after viewing the file, press q .

Note: Do not use less or more with executables (binary files), such as output files produced by compilers. Doing so will display garbage and may lock up your terminal.

lpr and lp -These commands print a file on a printer connected to the computer network.

The `lpr` command is used on BSD systems, and the `lp` command is used in System V. Both commands may be used on the UITS systems.

To print a file named myfile on a printer named lp1 with lpr, enter:

lpr -Plp1 myfile

To print the same file to the same printer with lp, enter:

lp -dlp1 myfile

Note: Do not print to a printer whose name or location is unfamiliar to you.

ls -This command will list the files stored in a directory.

To see a brief, multi-column list of the files in the current directory, enter:

ls
To also see "dot" files (configuration files that begin with a period, such as .login ), enter:

ls -a

To see the file permissions, owners, and sizes of all files, enter:

ls -la

If the listing is long and scrolls off your screen before you can read it, combine ls with the less utility, for
example:

ls -la | less

man -This command displays the manual page for a particular command.

If you are unsure how to use a command or want to find out all its options, you might want to try using `man` to view the manual page.

For example, to learn more about the ls command, enter:

man ls

To learn more about man, enter:

man man

If you are not sure of the exact command name, you can use man with the -k option to help you find the command you need. To see one line summaries of each reference page that contains the keyword you specify, enter:

man -k keyword

Replace keyword in the above example with the keyword which you want to reference. Also see

mkdir

This command will make a new subdirectory.

To create a subdirectory named mystuff in the current directory, enter:

mkdir mystuff

To create a subdirectory named morestuff in the existing directory named /tmp, enter:

mkdir /tmp/morestuff

Note: To make a subdirectory in a particular directory, you must have permission to write to that directory.

mv -This command will move a file. You can use `mv` not only to change the directory location of a file, but also to rename files.

Unlike the `cp` command, `mv` will not preserve the original file.

Note: As with the cp command, you should always use -i to make sure you do not overwrite an existing file.

To rename a file named oldname in the current directory to the new name newname, enter:

mv -i oldname newname

To move a file named hw1 from a subdirectory named newhw to another subdirectory named oldhw (both subdirectories of the current directory), enter:

mv -i newhw/hw1 oldhw

If, in this last operation, you also wanted to give the file a new name, such as firsthw, you would enter:

mv -i newhw/hw1 oldhw/firsthw

ps -The `ps` command displays information about programs (i.e., processes) that are currently running. Entered without arguments, it lists basic information about interactive processes you own. However, it also has many options for determining what processes to display, as well as the amount of information about each. Like `lp` and `lpr`, the options available differ between BSD and System V implementations. For example, to view detailed information about all running processes, in a BSD system, you would use `ps` with the following arguments:

ps -alxww
To display similar information in System V, use the arguments:

ps -elf

pwd

This command reports the current directory path. Enter the command by itself:

pwd

rm

This command will remove (destroy) a file. You should enter this command with the -i option, so that you'll be asked to confirm each file deletion. To remove a file named junk, enter:

rm -i junk

Note: Using rm will remove a file permanently, so be sure you really want to delete a file before you use rm.
To remove a non-empty subdirectory, rm accepts the -r option. On most systems this will prompt you to confirm the removal of each file. This behavior can be prevented by adding the -f option. To remove an entire subdirectory named oldstuff and all of its contents, enter:

rm -rf oldstuff

Note: Using this command will cause rm to descend into each subdirectory within the specified subdirectory and remove all files without prompting you. Use this command with caution, as it is very easy to accidently delete important files. As a precaution, use the ls command to list the files within the subdirectory you wish to remove. To browse through a subdirectory named oldstuff, enter:
ls -R oldstuff | less

rmdir

This command will remove a subdirectory. To remove a subdirectory named oldstuff, enter:

rmdir oldstuff

Note: The directory you specify for removal must be empty. To clean it out, switch to the directory and use the ls and rm commands to inspect and delete files.

set

This command displays or changes various settings and options associated with your Unix session.

To see the status of all settings, enter the command without options:

set

If the output scrolls off your screen, combine set with less:

set | less

The syntax used for changing settings is different for the various kinds of Unix shells; see the man entries for set and the references listed at the end of this document for more information.

vi

This command starts the vi text editor. To edit a file named myfile in the current directory, enter:

vi myfile

The vi editor works fairly differently from other text editors.

The very least you need to know to start using vi is that in order to enter text, you need to switch the program from command mode to insert mode by pressing i .

To navigate around the document with the cursor keys, you must switch back to command mode by pressing Esc.

To execute any of the following commands, you must switch from command mode to ex mode by pressing : (the colon key): Enter w to save; wq to save and quit; q! to quit without saving.

w and who

The w and who commands are similar programs that list all users logged into the computer. If you use w, you also get a list of what they are doing. If you use who, you also get the IP numbers or computer names of the terminals they are using.

Thursday, May 29, 2014

BHARAT OPERATING SYSTEM SOLUTIONS (BOSS)

Bharat Operating System Solutions (BOSS)

A computer operating system developed by the National Resource Centre for Free/Open Source Software (NRCFOSS) of India. Which is a free and open source OS.
BOSS GNU/Linux is also known by the acronym BOSS. The latest version of this operating system, BOSS GNU/Linux Version 4.0, was released in February 2011.
This software package has been described as "India's own PC operating system" the most meaningful product to come out of the Indian software industry in decades — and a work that a government department had done.
The software has also been endorsed by the Government of India for adoption and implementation on a national scale. (It was developed at Techno park Thiruvananthapuram Kerala INDIA).
BOSS GNU/Linux is an "LSB certified" Linux distribution: the software has been certified by the Linux Foundation for compliance with the Linux Standard Base standard.
BOSS GNU/Linux is derived from Debian. Debian uses the Linux kernel (the core of an operating system), but most of the basic operating system tools in Debian come from the GNU Project; hence the appendages GNU/Linux to Debian and BOSS.
The product is free software in the sense in which the term is used by the Free Software Foundation, and it is distributed under the GNU General Public License.
The latest desktop version of BOSS GNU/Linux is fully localised to eighteen Indian languages.

Contents

Versions

BOSS GNU/Linux has had five major releases till February 2011

Version	Code name	Kernel number	Desktop	Date of release
BOSS GNU/LinuxEvaluation	Sethu	2.6.14-2-smp	GNOME 2.8
BOSS GNU/Linux v1.0	Tarang	2.6.17-1-i386	GNOME 2.14
BOSS GNU/Linux v2.0	Anant	2.6.21-1-486	GNOME 2.18
BOSS GNU/Linux Server		2.6.21		Jan 2008
BOSS GNU/Linux v3.0	Tejas	2.6.22-3-486	GNOME 2.20 and KDE 3.5	Sep 2008
BOSS GNU/Linux v4.0	Savir	2.6.32-5-686	GNOME 2.30.2 and KDE 4.4.5	Feb 2011
BOSS GNU/Linux v5.0	Aasaan	2.6.32-5-686	GNOME 2.30.2 and KDE 4.4.5	To be announced

BOSS (Bharat Operating System Solutions) GNU/Linux distribution developed by C-DAC (Centre for Development of Advanced Computing) derived from Debian for enhancing the use of Free/ Open source software throughout India.
BOSSGNU/Linux - a key deliverable of NRCFOSS has upgraded from entry-level server to advanced server. It supports Intel and AMD x86/x86-64 architecture. BOSS GNU/Linux advanced server has unique features such as web server, proxy server, database server, mail server, network server, file and print server, SMS server, LDAP server.
BOSS GNU/Linux advanced server comprises administration tools such as webmin which is a web-based interface, Gadmin, PHP myadmin, PHP LDAP admin, PG admin.
BOSS GNU/Linux Version 4.0 is coupled with GNOME and KDE Desktop Environment with wide Indian language support and packages, relevant for use in the government domain.
Currently BOSS GNU/Linux Desktop is available in almost all the Indian Languages such as Assamese, Bengali, Gujarati, Hindi, Kannada, Malayalam, Marathi, Oriya, Punjabi, Sanskrit, Tamil, Telugu, Bodo, Urdu, Kashmiri, Maithili, Konkani, Manipuri which will enable the mainly non-English literate users in the country to be exposed to ICT and to use the computer more effectively.
The accessibility of BOSS Linux will have a constructive impact on the digital divide in India^] as more people can now have access to software in their local language to use the Internet and other information and communications technology (ICT) facilities. Community Information centers (CICs) and internet cafes will also benefit from BOSS GNU/Linux as this software can be utilized to power these outlets and is affordable and easy to install, use and support.
The latest version Boss 4.0 was released recently in 26 February 2011.

Available Indian languages

BOSS GNU/Linux is available in the following eighteen languages of India, among the twenty-two constitutionally recognized languages of India:

Assamese	Bengali	Bodo	Gujarati	Hindi
Kannada	Kashmiri	Konkani	Maithili	Malayalam
Manipuri	Marathi	Oriya	Punjabi	Sanskrit
Tamil	Telugu	Urdu	Arabic	Persian

The languages that are not available are Nepali, Sindhi, Dogri.