Can any function return NULL in C?

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Can any function return NULL in C?

You don’t. NULL is a macro representing a value of type void * . It is not an int , so a function returning int cannot return NULL .

Can NULL be returned?

Returning null Creates More Work A function that returns a null reference achieves neither goal. Returning null is like throwing a time bomb into the software. Other code must a guard against null with if and else statements.

Can a void function return NULL in C?

3 Answers. You can’t return NULL in a void function,because NULL is defined by #define NULL 0 in C++,(return 0 or NULL means that you return a value that is int or other type) void function means that it have no return value,you can write code: return; to exit a void function.

Can you return NULL for int?

int is a primitive, null is not a value that it can take on. You could change the method return type to return java. lang. Integer and then you can return null, and existing code that returns int will get autoboxed.

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How do I return a NULL object?

In Java, a null value can be assigned to an object reference of any type to indicate that it points to nothing. The compiler assigns null to any uninitialized static and instance members of reference type. In the absence of a constructor, the getArticles() and getName() methods will return a null reference.

How do I return a NULL pointer?

4 Answers

  1. You can return a null pointer if your function’s return type is a pointer.
  2. If the caller checks the return value and handles the case where the return value is null – then there shouldn’t be any problem.

Is it okay to return nothing?

null is the best thing to return if and only if the following following conditions apply: the null result is expected in normal operation. It could be expected that you may not be able to find a person in some reasonable circumstances, so findPerson() returning null is fine.

What to do instead of returning NULL?

Another way to avoid returning null is to use a Null object design pattern. A null object is an object without behavior like a stub that a developer can return to the caller instead of returning null value. The caller doesn’t need to check the order for null value because a real but empty Order object is returned.

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What does return null mean in C?

Returning null is usually the best idea if you intend to indicate that no data is available. An empty object implies data has been returned, whereas returning null clearly indicates that nothing has been returned.

What happens if a function returns nothing?

Void functions are created and used just like value-returning functions except they do not return a value after the function executes. You may or may not use the return statement, as there is no return value. Even without the return statement, control will return to the caller automatically at the end of the function.

Is returning NULL bad practice?

What does return null mean in C++?

NULL is a macro that expands to an implementation-defined null pointer constant. In the body of a function whose return type is a pointer type, return NULL; does exactly what you might reasonable expect: it causes the function to return a null pointer value of the appropriate type.

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How to return NULL value from an int array?

You shouldn’t return NULL, which is a zero constant of type int, but instead, return an empty instance of class Normal constructed by the no arg constructor, usually. Generally, it is good practice to additionally have the method isEmpty () defined. if (obj_of_class_Normal.isEmpty ()) //do something.

What is the example of null pointer in C?

The example of c is. int fun (int *ptr) {. return 10; } fun (NULL); It should be noted that NULL pointer is different from an uninitialized and dangling pointer. In a specific program context, all uninitialized or dangling or NULL pointers are invalid but NULL is a specific invalid pointer which is mentioned in C standard and has specific purposes.

How to return NULL value in header file?

Your class declaration in your header file should be terminated with a ;. You shouldn’t return NULL, which is a zero constant of type int, but instead, return an empty instance of class Normal constructed by the no arg constructor, usually. Generally, it is good practice to additionally have the method isEmpty () defined.