It isn't a question, sorry.
Pointer to Pointer is a double pointer, denoted by (**). Pointer stores the address of the variable and pointer to pointer stores the address of a pointer variable and syntax can be given as int **ptr2ptr;
A pointer to a function is the memory address that stores the address of a function, while the pointer itself is a function pointer.A pointer to a function might be defined as "int (*pf)(int, int);", while to actually point to the function, you would use a function pointer, such as "pf = &func;".
void as function return-type means no return value void as function parameter means no parameter void * as pointer type means generic pointer
When you call a function, the stack pointer is adjusted to cater for the function's arguments (if any), the caller's return address (mandatory), the function's local variables (if any) and the function's exception handlers (if any).
... are usable. void pointer (generic pointer) : a special type of pointer which point to some data of no specific types. void *p; null pointer : a special type of pointer which point nowhere. it is usually used to check if a pointer is pointing to a null or free the pointer during deallocation of memory in dynamic memory allocation; it is define by using the predefine constant NULL int *p=NULL; wild pointer : uninitialized pointer. it hold a garbage value. i.e it is not pointing to any memory location yet. dangling pointer: pointer pointing to a destroyed variable. it usually happen during dynamic memory allocation when the object is destroyed but not free and the pointer is still pointing to the destroy object.
Usable. A prominent example is param argv of function main.
*function();this declares a pointer function!
Pointer to Pointer is a double pointer, denoted by (**). Pointer stores the address of the variable and pointer to pointer stores the address of a pointer variable and syntax can be given as int **ptr2ptr;
function pointer is a variable that hold the address of any function which declared in the program but function pointer is the array of the function that accept the run time size of the function.
A pointer to a function is the memory address that stores the address of a function, while the pointer itself is a function pointer.A pointer to a function might be defined as "int (*pf)(int, int);", while to actually point to the function, you would use a function pointer, such as "pf = &func;".
void as function return-type means no return value void as function parameter means no parameter void * as pointer type means generic pointer
If you mean example, then it is argv, which is the second parameter of function main.
When you call a function, the stack pointer is adjusted to cater for the function's arguments (if any), the caller's return address (mandatory), the function's local variables (if any) and the function's exception handlers (if any).
Example: void foo( MyClass& object ){} // function with call by reference signature MyClass* p = new MyClass(); // instantiate a pointer to MyClass foo( *p ); // call by reference using the pointer
... are usable. void pointer (generic pointer) : a special type of pointer which point to some data of no specific types. void *p; null pointer : a special type of pointer which point nowhere. it is usually used to check if a pointer is pointing to a null or free the pointer during deallocation of memory in dynamic memory allocation; it is define by using the predefine constant NULL int *p=NULL; wild pointer : uninitialized pointer. it hold a garbage value. i.e it is not pointing to any memory location yet. dangling pointer: pointer pointing to a destroyed variable. it usually happen during dynamic memory allocation when the object is destroyed but not free and the pointer is still pointing to the destroy object.
Parameters are the formal arguments of a function, as defined by the function. When you pass arguments to a function, those arguments are assigned to the function's parameters, either by value or by reference, depending on how the parameters are declared in the function. The following example explains both: void foo( int param ) { // param is a by value parameter, which is a copy of the argument passed to it. } void bar( int& param ) { // param is a reference parameter, which references the argument passed to it. } int main() { int arg = 100; foo( arg ); bar( arg ); return( 0 ); } Note that passing a pointer is the same as passing an int by value: the pointer's value is passed to the function, not the pointer itself. To pass a pointer by reference, you must pass a pointer to pointer and the function's parameter must accept a pointer to pointer.
Here is an example for a variable, which is a function (function-pointer, actually): int (*myfun)(const char *s); myfun = puts; myfun ("Hello, world");