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Standard C/C++
C and C++ are the world's most important
programming languages.
Indeed, to be a professional programmer today implies proficiency in these two languages.
They are the foundation upon which modern programming is built.
C was invented by Dennis Ritchie in the 1970s. C is a middle-level language.
It combines the control structures of a high-level language with the ability to manipulate bits, bytes,
and pointers (addresses). This, C gives the programmer nearly complete control
over the machine. C was first standardized late in 1989 when the American National Standards
Institute (ANSI) standard for C was adopted. This version of C is commonly referred to
as C89. This standard was also adopted by ISO (International Standards Organization).
C89 was amended slightly in 1995.
C++ was created by Bjarne Stroustrup, beginning in 1979. The development and refinement of C++
was a major effort, spanning the 1980s and most of the 1990s. Finally, in 1998 an ANSI/ISO
standard for C++ was adopted. In general terms, C++ is the object-oriented version of C. C++ is
built upon the foundation of C89, including its 1995 amendments. In fact, the
version of C defined by C89 is commonly referred to as the "C subset of C++."
Although C++ began as a set of object-oriented extensions to C,
it soon expanded into being a programming language in its own right.
Today, C++ is nearly twice the size of the C language. Needless to say,
C++ is one of the most powerful computer languages ever devised.
In 1999, a new ANSI/ISO standard for C was adopted. This version is called C99.
It includes a number of refinements and several new features. Some of these "new"
features were borrowed from C++, but some are entirely new innovations. Thus,
several of the elements added by C99 are incompatible with C++. This means
that with the advent of C99, Standard C is no longer a pure subset of C++.
Fortunately, many of the incompatibilities relate to special-use features
that are readily avoided. Thus, it is still easy to write code that is
compatible with both C and C++. At the time of this writing, no major compiler
currently accepts all of the C99 additions, but this is sure to change.
The following table synopsizes the relationships between C89, C99, and C++.
C89 |
The original ANSI/ISO standard for C. C89 is what most
programmers today think of as C. |
C++ |
The object-oriented version of C. The current ANSI/ISO standard for C++
is built upon C89. Thus, C89 forms a subject of C++.
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C99 |
The latest standard for C. Includes all of C89, but adds several
new features. Some of the new features are not supported by the
current standard for C++.
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Herbert Schildt
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