Assignment 1 WXGA 6101

1
Assignment 1WXGA 6101

• C Programming
• By
• Theivarayan Prakash Somasundaram
• WGA 030083

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History of C language
Jointly developed by the Mathematical Laboratory
at the University of Cambridge and the University
of London Computer Unit during the 1960s
Combined Programming Language (CPL)
Basic CPL (BCPL)
Created at 1967 as a scaled down version of CPL.
Developed by Martin Richard
B
Developed by Ken Thompson at Bell Laboratories in
1970 specifically for systems programming
C
Developed by Dennis Ritchie at Bell Laboratories
in 1972
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Why design C ?

• B, developed by Ken Thompson was used for
  development of the Unix system. Dennis Ritchie
  later created a new language called C which had
• concise syntax
• powerful mix of high-level functionality
• features required to program an operating system
• Most of the components of Unix were eventually
  rewritten in C

Where is it in use today ?

• Operating systems (Unix)
• Control and embedded systems
• Computer Games

Programming paradigm

• Structured programming

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What application areas is it most suited for ?

• Embedded systems
• Backend processing
• Computer Games

C features ?

• Powerful
• Fast program execution
• Allows low level access
• Pointer manipulation capabilities
• Modular

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What are the claims made of its security,
portability, efficiency, extensibility/maintainabi
lity ?

• Security - Cs security depends on how the
  program is developed.
• Portability - C is capable in running in multiple
  operating systems including Windows and Unix
• Efficiency - C's power and fast program execution
  comes from it's ability to access low level
  commands
• Extensibility/maintainability - C considered
  highly extensive and maintainable provided the
  program is maintained by an experienced
  programmer. This is because a slight mistake
  using pointers can cause buffer overflows.

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C Compilation/Interpretation/Execution model
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Scalar data objects
Composite objects
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Structured objects
Abstract data objects
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Active objects
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Final Evaluation

• Do you have any basis to agree or disagree with
  any claims made of its security, portability,
  efficiency, extensibility/maintainability?
• I agree with all the claims as even though many
  other languages has been introduced in the
  market, C is still widely used in the industry.
• What aspect of this language did you find most
  difficult to learn/understand?
• Pointers.
• How would you rate the programming environment?
  compiler/interpreter messages?
• I use VC as the compiler. The IDE environment
  and interpreter messages are simple and straight
  forward.
• Would you use this language again and if so what
  for?
• Yes, for backend processing.
• Design mistakes (in your opinion or the opinion
  of others)? Have they been corrected in other
  languages that were a follow-on. What if anything
  is missing in your opinion?
• In my opinion the only problem with C language is
  that it does not handle buffer overflow which
  causes the program to crash. This however is not
  a problem for advanced programmers.

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References

• H.M.Deitel and P.J.Deitel, C How To Program,
  Prentice Hall International
• Ivor Horton, Beginning C, Wrox Publication
• http//cm.bell-labs.com/cm/cs/who/dmr/chist.html
• http//www.cs.bell-labs.com/who/dmr/index.html
• http//www.engin.umd.umich.edu/CIS/course.des/cis4
  00/c/c.html
• http//computer.howstuffworks.com/c1.htm
• http//www.livinginternet.com/i/iw_unix_c.htm
• http//www.kuro5hin.org/story/2004/2/7/144019/8872