Introduction to the C Tutorial
The programming language C was originally developed by Dennis Ritchie of Bell Laboratories and was designed to run on a PDP-11 with a UNIX operating system. Although it was originally intended to run under UNIX, there has been a great interest in running it under the MS-DOS operating system and specifically on the IBM PC and compatibles. It is an excellent language for this environment because of the simplicity of expression, the compactness of the code, and the wide range of applicability.
It is not a good "beginning" language because it is somewhat cryptic in nature. It allows the programmer a wide range of operations from high level down to a very low level approaching the level of assembly language. There seems to be no limit to the flexibility available. One experienced C programmer made the statement, "You can program anything in C", and the statement is well supported by my own experience with the language. Along with the resulting freedom however, you take on a great deal of responsibility because it is very easy to write a program that destroys itself due to the silly little errors that the Pascal compiler will flag and call a fatal error. In C, you are very much on your own as you will soon find.
Since C is not a beginners language, I will assume you are not a beginning programmer, and I will not attempt to bore you by defining a constant and a variable. You will be expected to know these basic concepts. You will, however, be expected to know nothing of the C programming language.
I will begin with the most basic concepts of C and take you up to the highest level of C programming including the usually intimidating concepts of pointers, structures, and dynamic allocation. To fully understand these concepts, it will take a good bit of time and work on your part because they not particularly easy to grasp, but they are very powerful tools. Enough said about that, you will see their power when we get there, just don't allow yourself to worry about them yet.
Programming in C is a tremendous asset in those areas where you may want to use Assembly Language but would rather keep it a "simple to write" and "easy to maintain" program. It has been said that a program written in C will pay a premium of a 50 to 100% increase in runtime because no language is as compact or fast as Assembly Language. However, the time saved in coding can be tremendous, making it the most desirable language for many programming chores. In addition, since most programs spend 90 percent of their operating time in only 10 percent or less of the code, it is possible to write a program in C, then rewrite a small portion of the code in Assembly Language and approach the execution speed of the same program if it were written entirely in Assembly Language.
Even though the C language enjoys a good record when programs are transported from one implementation to another, there are differences in compilers as you will find anytime you try to use another compiler. Most of the differences become apparent when you use nonstandard extensions such as calls to the DOS BIOS, but even these differences can be minimized by careful choice of programming means.
Throughout this tutorial, every attempt will be made to indicate to you what constructs are available in every C compiler because they are part of the accepted standard of programming practice.
Modern C compilers are very capable systems, but due to the tremendous versatility of a C compiler, it could be very difficult for you to learn how to use it effectively. If you are a complete novice to programming, you will probably find the installation instructions somewhat confusing.
This tutorial cannot cover all aspects of programming in C, simply because there is too much to cover, but it will instruct you in all you need for the majority of your programming in C. You will receive instruction in all of the programming constructs in C, but what must be omitted are methods of programming since these can only be learned by experience. More importantly, it will teach you the vocabulary of C so that you can go on to the more advanced techniques of using the programming language C.
It is not a good "beginning" language because it is somewhat cryptic in nature. It allows the programmer a wide range of operations from high level down to a very low level approaching the level of assembly language. There seems to be no limit to the flexibility available. One experienced C programmer made the statement, "You can program anything in C", and the statement is well supported by my own experience with the language. Along with the resulting freedom however, you take on a great deal of responsibility because it is very easy to write a program that destroys itself due to the silly little errors that the Pascal compiler will flag and call a fatal error. In C, you are very much on your own as you will soon find.
Since C is not a beginners language, I will assume you are not a beginning programmer, and I will not attempt to bore you by defining a constant and a variable. You will be expected to know these basic concepts. You will, however, be expected to know nothing of the C programming language.
I will begin with the most basic concepts of C and take you up to the highest level of C programming including the usually intimidating concepts of pointers, structures, and dynamic allocation. To fully understand these concepts, it will take a good bit of time and work on your part because they not particularly easy to grasp, but they are very powerful tools. Enough said about that, you will see their power when we get there, just don't allow yourself to worry about them yet.
Programming in C is a tremendous asset in those areas where you may want to use Assembly Language but would rather keep it a "simple to write" and "easy to maintain" program. It has been said that a program written in C will pay a premium of a 50 to 100% increase in runtime because no language is as compact or fast as Assembly Language. However, the time saved in coding can be tremendous, making it the most desirable language for many programming chores. In addition, since most programs spend 90 percent of their operating time in only 10 percent or less of the code, it is possible to write a program in C, then rewrite a small portion of the code in Assembly Language and approach the execution speed of the same program if it were written entirely in Assembly Language.
Even though the C language enjoys a good record when programs are transported from one implementation to another, there are differences in compilers as you will find anytime you try to use another compiler. Most of the differences become apparent when you use nonstandard extensions such as calls to the DOS BIOS, but even these differences can be minimized by careful choice of programming means.
Throughout this tutorial, every attempt will be made to indicate to you what constructs are available in every C compiler because they are part of the accepted standard of programming practice.
Modern C compilers are very capable systems, but due to the tremendous versatility of a C compiler, it could be very difficult for you to learn how to use it effectively. If you are a complete novice to programming, you will probably find the installation instructions somewhat confusing.
This tutorial cannot cover all aspects of programming in C, simply because there is too much to cover, but it will instruct you in all you need for the majority of your programming in C. You will receive instruction in all of the programming constructs in C, but what must be omitted are methods of programming since these can only be learned by experience. More importantly, it will teach you the vocabulary of C so that you can go on to the more advanced techniques of using the programming language C.
