practice-c

Revising C lang

The codes here are just for learning purpose, there may be better ways to write them.

TODO

• Types, Operators and Expressions
  • Data types and sizes
  • Enum data type
  • Type conversions
  • Constants
  • Operators (Assignment, bit and ternary)
  • Increment and decrement
  • Precedence
• Flow Control
  • if/else
  • switch
  • while
  • do-while
  • for
  • Examples
• Functions
  • Examples
• Recursion
• Pointers
  • Introduction
  • Functions
  • Arrays
  • Pointer arithmentic
  • Character ararys
  • Array of pointers and multidimensional arrays
  • Pointer to functions
  • Examples
• Arrays
• Strings
  • Basic operations on string
  • Examples
    • Compare
    • Concat
    • Copy
    • Count
    • itoa
    • atoi
• Storage Classes
  • Register
  • Static
  • Global
• Structures and Unions
  • Malloc
    • Process memory model
• Input/Output
• File Input/Output

Pointers to functions

int *fp(int, int);

its not the pointer to the function because
() has higher precedence to * hence its interpreted
as fp as function which returns a pointer to an int.

int sum(int, int);
     |
int (*fp)(int, int);

since, () is left associative hence above
is pointer to a function which takes two 
ints and returns an int.


fp = sum
s = sum(5, 6)
s = (*fp)(5, 6)

The () is left associative hence

Malloc

void* malloc(int);

example:

Allocate a memory block of 10 and return the address.

int *p = (int*) malloc(10);

But size of int is platform dependant, hence:

int *p = (int*) malloc(5 * size(int));