Introduction to c

History of the c programming language

C is a general-purpose programming language with features economy of expression, modern flow control and data structures, and a rich set of operators.

C was developed at Bell Laboratories in 1972 by Dennis Ritchie. Many of its principles and ideas were taken from the earlier language B and B's earlier ancestors BCPL and CPL. CPL ( Combined Programming Language ) was developed with the purpose of creating a language that was capable of both high level, machine independent programming and would still allow the programmer to control the behavior of individual bits of information.

There are some of C's characteristics that define the language and also have lead to its popularity as a programming language. Naturally we will be studying many of these aspects throughout the course.

• Small size
• Extensive use of function calls
• Loose typing -- unlike PASCAL
• Structured language
• Low level (BitWise) programming readily available
• Pointer implementation - extensive use of pointers for memory, array, structures and functions.

C has now become a widely used professional language for various reasons.

• It has high-level constructs.
• It can handle low-level activities.
• It produces efficient programs.
• It can be compiled on a variety of computers.

Its main drawback is that it has poor error detection which can make it off putting to the beginner. However diligence in this matter can pay off handsomely since having learned the rules of C we can break them. Not many languages allow this. This if done properly and carefully leads to the power of C programming.

C's power and flexibility soon became apparent. Because of this, the Unix operating system which was originally written in assembly language, was almost immediately re-written in C ( only the assembly language code needed to "bootstrap" the C code was kept ). During the rest of the 1970's, C spread throughout many colleges and universities because of it's close ties to Unix and the availability of C compilers. Soon, many different organizations began using their own versions of C causing compatibility problems. In response to this in 1983, the American National Standards Institute ( ANSI ) formed a committee to establish a standard definition of C which became known as ANSI Standard C. Today C is in widespread use with a rich standard library of functions.

The integrated development environment of c++ 3.0

Start Turbo C++ IDE

Change to directory C:\TC\BIN

Run TC.EXE

The screen should look like [link]

Select the File menu to create a new file or open an existing file to edit.

Choose a file to open. This screen allow you to change to your directory.

Compile and run a program

To compile a program , use F9 or the compile menu

To run a program, use the run menu or press Ctrl + F9

If your program have no syntax error, the user screen look like in [link]

To exit from IDE, select the file menu, choose quit or press Alt+X

Basic components of c programs

Symbols

A C program consists of the following characters: