What is C

1
What is C

• Introduction to the C Programming Language

2
Outline

• History
• What is C
• How does C relate to other OO languages
• Types of applications for C
• Components of MSs Visual C 6.0
• Advantages / Disadvantages of C

3
History of C

• 1967 "B" and BCPL developed (typeless)
• 1972 C language developed at Bell Labs
• Dennis Ritchie wrote C for Unix OS
• Needed C for work with Unix
• late 70s C becomes popular for OS development
  by many vendors
• Many variants of the language developed
• ANSI standard C in 1987-89

4
History of C (continued)

• early 80s Bjarne Stroustrup adds OO features to
  C creating C
• 90s continued evolution of the language and its
  applications
• preferred language for OS and low level
  programming
• popular language for application development
• low level control and high level power

5
Conceptually what is C

• Alternatives
• is it C, with lots more options and features?
• is it an OO programming language with C as its
  core?
• is it a development environment?
• On most systems it is a development environment,
  language, and library, used for both procedural
  and object oriented programming, that can be
  customized and extended as desired

6
Versions of C

• ANSI C
• Microsoft C (MS Visual C 6.0)
• Other vendors Borland, Symantec, Turbo,
• Many older versions (almost annual) including
  different version of C too
• Many vendor specific versions
• Many platform specific versions

7
Characteristics of C as a Computer Language

• Procedural
• Object Oriented
• Extensible
• ...

8
Other OO Languages

• Smalltalk
• pure OO language developed at PARC
• Java
• built on C/C
• objects and data types
• Eifel and others

9
What you can do with C

• Apps (standalone, Web apps, components)
• Tiered apps
• Active desktop (Dynamic HTML, incl Web)
• Access to MFC
• Create new controls
• Create apps with "look and feel" of IE4
• ActiveX documents (charts, graphs, etc.)
• Data access (OLE, e-mail, files, ODBC)
• Integrate components w/ other languages

10
Microsofts C

• Development Environment
• project mgmt, editor, debugging tools, user
  interface to tools
• Visual Studio 6.0
• Language (
• compiler, linker, loader, etc.
• Visual C 6.0
• Libraries
• std libraries, iostream, iomanip, stdio, time,
  string, math, etc.
• Standard Template Library (STL)

11
Disadvantages of C

• Tends to be one of the less portable languages
• Complicated!!!
• 40 operators, intricate precedence, pointers,
  etc.
• can control everything
• many exceptions and special cases
• tremendous libraries both standard, vendor
  specific, and available for purchase, but all are
  intricate
• Aspects above can result in high cost,
  maintenance and reliability problems

12
Advantages of C

• Available on most machines
• Can get good performance
• Can get small size
• Can manage memory effectively
• Can control everything
• Good supply of programmers
• Suitable for almost any type of program (from
  systems programs to applications)

13
Steps in Developing a C Program

• Plan
• Edit (uses integrated editor)
• Compile (converts to binary)
• Link (resolves external references)
• Load (places into memory)
• Run (transfers control, executes)
• IDE reports errors at this step must fix them

14
Objectives for a C System

• Solves correct problem
• Correct solution
• but also
• Clear documentation (internal and external)
• Understandable code
• Maintainable and extendable system
• Reusable code
• how about
• succinct code?? performance??