Programming Fundamentals and Programming Languages Concepts Translators

Programming Fundamentals and Programming Languages Concepts Translators

• 1.
  Translators • A translatoris a computer program that performs the translation of a program written in a given programming language into a functionally equivalent program in a different computer language, without losing the functional or logical structure of the original code • These include translations between high-level and human-readable computer languages such as C++ and Java , intermediate-level languages such as Java byte code, low-level languages such as the assembly language and machine code,
• 2.
  Types of Translators Assembler: •An assembler translates assembly language into machine code. Interpreter: • An interpreter program executes other programs directly, running through program code and executing it line-by-line. Compiler: • A Compiler is a computer program that translates code written in a high level language to a lower level language, object/machine code.
• 3.
  Simple C Program /*A first C Program*/ #include <stdio.h> void main() { printf("Hello World n"); }
• 4.
  Simple C Program /*A first C Program*/ #include <stdio.h> #include <conio.h> void main() { printf("Hello World n"); getch(); }
• 5.
  Simple C Program •Line 1: #include <stdio.h> • As part of compilation, the C compiler runs a program called the C preprocessor. The preprocessor is able to add and remove code from your source file. • In this case, the directive #include tells the preprocessor to include code from the file stdio.h. • This file contains declarations for functions that the program needs to use. A declaration for the print function is in this file.
• 6.
  Simple C Program •Line 2: void main() • This statement declares the main function. • C program can contain many functions but must always have one main function. • A function is a self-contained module of code that can accomplish some task. • "void" specifies the return type of main. In this case, nothing is returned to the operating system.
• 7.
  Simple C Program •Line 3: { • This opening bracket denotes the start of the program.
• 8.
  Simple C Program •Line 4: printf("Hello Worldn"); • printf is a function from a standard C library that is used to print strings to the standard output, normally your screen. • The "n" is a special format modifier that tells the printf to put a line feed at the end of the line. • If there were another printf in this program, its string would print on the next line.
• 9.
  Simple C Program •Line 5: } • This closing bracket denotes the end of the program.
• 10.
  Basics of CEnvironment • C systems consist of 3 parts • Environment • Language • C Standard Library • Development environment has 6 phases  Edit - Writing the source code by using some IDE or editor  Pre-processor - Already available routines  Compile - translates or converts source to object code for a specific platform ie., source code -> object code  Link - resolves external references and produces the executable module  Load – put the program into the memory  Execute – runs the program
• 11.
  Basics of CEnvironment Editor DiskPhase 1 Program edited in Editor and stored on disk Preprocessor DiskPhase 2 Preprocessor program processes the code Compiler DiskPhase 3 Creates object code and stores on disk Linker DiskPhase 4 Links object code with libraries and stores on disk
• 12.
  Basics of CEnvironment LoaderPhase 5 Puts program in memory Primary memory CPUPhase 6 Takes each instruction and executes it storing new data values Primary memory
• 13.
  Executing a CProgram Steps involved in execution are • Creating the program • Compiling the program • Linking the program with functions that are needed from the C library • Executing the program
• 14.
  Executing a CProgram Edit Program Source Code Compile Object Code Link Object Code Executable Library Files