The Birth of Modern Programming: C
The C language shook the computer world. Its impact should not be underestimated, because
it fundamentally changed the way programming was approached and thought about. The
creation of C was a direct result of the need for a structured, efficient, high-level language that
could replace assembly code when creating systems programs. As you probably know, when
a computer language is designed, trade-offs are often made, such as the following:
· Ease-of-use versus power
· Safety versus efficiency
· Rigidity versus extensibility
Prior to C, programmers usually had to choose between languages that optimized one set of
traits or the other. For example, although FORTRAN could be used to write fairly efficient
programs for scientific applications, it was not very good for system code. And while BASIC
was easy to learn, it wasn't very powerful, and its lack of structure made its usefulness
questionable for large programs. Assembly language can be used to produce highly efficient
programs, but it is not easy to learn or use effectively. Further, debugging assembly code
can be quite difficult.
Another compounding problem was that early computer languages such as BASIC,
COBOL, and FORTRAN were not designed around structured principles. Instead, they
relied upon the GOTO as a primary means of program control. As a result, programs
written using these languages tended to produce "spaghetti code"--a mass of tangled
jumps and conditional branches that make a program virtually impossible to understand.
While languages like Pascal are structured, they were not designed for efficiency, and failed
to include certain features necessary to make them applicable to a wide range of programs.
(Specifically, given the standard dialects of Pascal available at the time, it was not practical
to consider using Pascal for systems-level code.)
So, just prior to the invention of C, no one language had reconciled the conflicting
attributes that had dogged earlier efforts. Yet the need for such a language was pressing. By
the early 1970s, the computer revolution was beginning to take hold, and the demand for
software was rapidly outpacing programmers' ability to produce it. A great deal of effort
was being expended in academic circles in an attempt to create a better computer language.
But, and perhaps most importantly, a secondary force was beginning to be felt. Computer
hardware was finally becoming common enough that a critical mass was being reached.
No longer were computers kept behind locked doors. For the first time, programmers
were gaining virtually unlimited access to their machines. This allowed the freedom to
experiment. It also allowed programmers to begin to create their own tools. On the eve
of C's creation, the stage was set for a quantum leap forward in computer languages.
Invented and first implemented by Dennis Ritchie on a DEC PDP-11 running the UNIX
operating system, C was the result of a development process that started with an older
language called BCPL, developed by Martin Richards. BCPL influenced a language called
B, invented by Ken Thompson, which led to the development of C in the 1970s. For many
years, the de facto standard for C was the one supplied with the UNIX operating system
and described in The C Programming Language by Brian Kernighan and Dennis Ritchie
(Prentice-Hall, 1978). C was formally standardized in December 1989, when the American
National Standards Institute (ANSI) standard for C was adopted.
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