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You cannot delete an uninitialized pointer, because there is no allocation for the object, and the pointer contains garbage. That includes the case where you attempted allocation and failed, but deletion is safe in that case because a NULL pointer is "safe" to delete, even though it does not point at anything.
What else can I help you with?
Algorithm to delete?
The only way to delete objects in an object oriented programming language (unless they were created in heap memory) is for the object to go out of scope. If the object is declared in the heap, in c++ you would use delete[] ptr; or delete ptr; where ptr is a pointer to your object.
Should you explicitly call a destructor in C programming?
Not to be pedantic, but you cannot call a destructor explicitly. Destructors are implicitly called when an object falls from scope or when you delete a pointer to an object. Any object created dynamically (with the new keyword) must be deleted as soon as you are finished with it, and before the pointer falls from scope. In this sense, you are explicitly calling the object's destructor, however it's really being called implicitly by you deleting the pointer. It's also good practice to explicitly NULL your pointer immediately after deleting the object it pointed to. An object reference is destroyed automatically when the reference falls from scope. If you have a pointer to that reference, do not delete the pointer, but do assign it to NULL as soon as possible to prevent any access to the deleted object. If you do delete a pointer to a reference that's still in scope, you will render the reference NULL and a NULL reference will render your program invalid.
How do you use delete function in inheritence in classes using c plus plus?
You use delete to release the memory occupied by an object that is being pointed to by the pointer you delete. Provided all base classes have a virtual destructor, it doesn't matter what the type of pointer you actually delete is, so long as it is a type of class from which the object is actually derived. The destructor from the most-inherited class (the object itself) will be called first, which calls the destructors of its immediate base classes, and theirs, and so on until the object is completely released from memory.Note that you must not delete pointers to object references -- they must be nullified (not deleted) when they are no longer required. The referenced object will be deleted automatically when it falls from scope.
What is a bit copy?
A bit copy of an object is an exact, bit-by-bit, copy of that object. The default copy constructor generated by the compiler makes a bit copy. This is potentially a problem if the object contains pointers to other objects... A bit copy of a pointer copies the pointer, but not its data. This means that you have two pointers pointing at the same object in memory. If you delete one of them, the other becomes invalid, and this can (usually does) cause corruption. If an object contains a pointer, the object's copy constructor should provide for proper allocation and copying of any pointed to objects within that object.
When you let your pointer linger over an object the pointer is?
The pointer is non-NULL.
Algorithm to delete?
The only way to delete objects in an object oriented programming language (unless they were created in heap memory) is for the object to go out of scope. If the object is declared in the heap, in c++ you would use delete[] ptr; or delete ptr; where ptr is a pointer to your object.
Should you explicitly call a destructor in C programming?
Not to be pedantic, but you cannot call a destructor explicitly. Destructors are implicitly called when an object falls from scope or when you delete a pointer to an object. Any object created dynamically (with the new keyword) must be deleted as soon as you are finished with it, and before the pointer falls from scope. In this sense, you are explicitly calling the object's destructor, however it's really being called implicitly by you deleting the pointer. It's also good practice to explicitly NULL your pointer immediately after deleting the object it pointed to. An object reference is destroyed automatically when the reference falls from scope. If you have a pointer to that reference, do not delete the pointer, but do assign it to NULL as soon as possible to prevent any access to the deleted object. If you do delete a pointer to a reference that's still in scope, you will render the reference NULL and a NULL reference will render your program invalid.
How do you use delete function in inheritence in classes using c plus plus?
You use delete to release the memory occupied by an object that is being pointed to by the pointer you delete. Provided all base classes have a virtual destructor, it doesn't matter what the type of pointer you actually delete is, so long as it is a type of class from which the object is actually derived. The destructor from the most-inherited class (the object itself) will be called first, which calls the destructors of its immediate base classes, and theirs, and so on until the object is completely released from memory.Note that you must not delete pointers to object references -- they must be nullified (not deleted) when they are no longer required. The referenced object will be deleted automatically when it falls from scope.
What is diffrent between object pointer and this pointer?
'this' is an object-pointer: it points to the current object (usable only in non-static methods).
What is dangling pointer reference in c plus plus?
A dangling pointer (we also use the terms stray pointer and wild pointer) is created whenever we call delete on a pointer and then try to use the pointer without reassigning it.We can also create dangling pointers inadvertently by calling a rogue function that returns a pointer to an object that is local to the function we are calling. The object will fall from scope when the function returns so the pointer is left dangling.Note that there is no such thing as a dangling pointer reference. Pointers and references are not the same. A reference is merely an alias to an object -- it consumes no memory beyond the object it refers to. Whereas a pointer is a variable that may contain the address of an object, but it requires additional memory to do so (4 bytes on 32-bit architecture). Pointers may be NULL, references can never be NULL. Pointers to valid objects require indirection, references do not. References are the preferred method of accessing an object's members, not least because they are easier to work with.
What is a bit copy?
A bit copy of an object is an exact, bit-by-bit, copy of that object. The default copy constructor generated by the compiler makes a bit copy. This is potentially a problem if the object contains pointers to other objects... A bit copy of a pointer copies the pointer, but not its data. This means that you have two pointers pointing at the same object in memory. If you delete one of them, the other becomes invalid, and this can (usually does) cause corruption. If an object contains a pointer, the object's copy constructor should provide for proper allocation and copying of any pointed to objects within that object.
When you let your pointer linger over an object the pointer is?
The pointer is non-NULL.
Why pointer is not an object?
A pointer in itself is not an object, because it is not an instance of a class. Of course you can define a class which has only one member, which is a pointer. class Pointer { public void *ptr; }; Pointer p, q, r;
What is smart pointer?
Smart pointers are C++ regular pointers except that they automatically delete the object pointed to at the appropriate time.Thus ensuring proper destruction of dynamically allocated objects.
When does this pointer get created?
When we call non static method with respect to class object then this pointer is created which keep the reference of that object.
Where string is stored on Heap or Stack in java?
A String is treated as an object, meaning there is an object on the heap. Of course, the variable you define is a pointer to the object, and it is stored on the stack.A String is treated as an object, meaning there is an object on the heap. Of course, the variable you define is a pointer to the object, and it is stored on the stack.A String is treated as an object, meaning there is an object on the heap. Of course, the variable you define is a pointer to the object, and it is stored on the stack.A String is treated as an object, meaning there is an object on the heap. Of course, the variable you define is a pointer to the object, and it is stored on the stack.
Is it possible to delete a const object in C plus plus?
Yes. However, making a const pointer seems rather pointless, as you will be able to allocate and deallocate memory for it, but you will be unable to change the contents.
Different types of pointers in c language?
... 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.
When putting an object on a spring scale the pointer shows the object's what?
When putting an object on a spring scale the pointer is going to show that objects weight. So the answer would be WEIGHT. Like for example when you are in your bathroom and you step on the scale , the pointer is going to show how much you weigh.
What is null point?
A pointer variable which is declared but not initialized is called a NULL POINTER.ex: int *p;Please don't use the above. A NULL pointer is a specific value assigned to a pointer, just like any other value. NULL is a language-specific designation, and is guaranteed to be comparable to, unlike uninitialized variables, which can have any value.That is:int *a;int *b = NULL;int *c = (int *) malloc(sizeof(char));( a c) is NEVER true.NULL is a reserved word in most high-level languages, and indicates a specific value for assignment. It is commonly used to indicate that something has not yet been assigned a "real" value, or has had its contents deleted. It is an EXPLICIT value, and not just "undefined".In the context of pointers (which, remember, are really memory location addresses), a NULL pointer is one which has NO value, and thus does NOT point to any memory location. The difference between an uninitialized pointer and a NULL pointer is that most common languages do not specify what value an uninitialized pointer has upon creation (many, such as C, are assigned a random value), while a NULL pointer explicitly has NO value (which is the meaning of NULL).Many modern languages and compilers will assign NULL to a pointer upon initialization, but don't count on it. It is sloppy programming to do so, and can lead to many hard-to-find errors.
When the destructor may be invoked in c?
C is not an object-oriented language -- there are no destructors. In C++, however, an object's destructor is invoked automatically when the object falls from scope. The destructor can also be invoked by manually deleting a raw pointer to the object (or one of its base classes), however you should only ever use the delete operator if the object was instantiated with the new operator, and only after all references or pointers to the object have fallen from scope. The safest way to manage raw pointers is to use a resource handle or smart pointer.
Java does not support pointers then what is null pointer exception?
A null pointer exception is thrown when you are trying to manipulate an object that is null. It is just the name and does not have any relevance to the pointers as in C Example: ArrayList lst = null; Object obj = lst.get(0); In the first line we have declared an array list. Without initializing it we have tried to access the element in the 0th position. This would cause a null pointer exception.
Which pointer do you use to resize a chart object?
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Are pointers inherited?
All elements of a class are inherited, including pointers. This includes methods such as constructors and destructors that manipulate the pointers. However, the question seems related to copying, instead of to inheritance... If you do not provide a copy constructor, the compiler will provide one, but that code will only copy the pointers - unless the pointers are some kind of smart pointer class, it will not copy the objects to which they point. This results in two pointers referring to one object. The danger is in what happens when one pointer is deleted, or in what happens when one pointer's object is modified. You have to decide how to handle mutability and ownership, the latter including who gets to execute the destructor or delete sequence for the pointer? One solution is reference pointers using smart pointer technology. The pointer/object itself has a reference count which is incremented each time an address of the object is taken, such as in copying a pointer. The reference count is decremented each time a pointer is deleted and, when it reaches zero, the object itself is deleted. You can also decide if executing a mutating operation results in a second copy of the object being made, or if you can tolerate having another pointer refer to an object that has changed. These techniques can balance cost of operation against protection against memory corruption, but they do come with their own cost for design, implementation, and testing.
What is an array of pointers to pointers?
A pointer is a variable that stores value of address of a variable. Since a pointer itself is a variable, it is allocated a memory location.Pointer to pointer means a pointer which points to the address of a pointer. In other words a pointer to a pointer has the address of the address of a variable.We can have pointers to int, and pointers to char, and pointers to any structures we've defined, and in fact pointers to any type in C, it shouldn't come as too much of a surprise that we can have pointers to other pointers. If we're used to thinking about simple pointers, and to keeping clear in our minds the distinction between the pointer itself and what it points to, we should be able to think about pointers to pointers, too, although we'll now have to distinguish between the pointer, what it points to, and what the pointer that it points to points.
