Can we declare extern locally?

Local variables can be declared extern in some cases

1/5 “Storage-class specifiers” says: The declaration of an identifier for a function that has block scope shall have no explicit storage-class specifier other than extern. Then for what it means to add extern to a local variable, 6.2.

What is extern declaration?

the extern keyword is used to extend the visibility of variables/functions. Since functions are visible throughout the program by default, the use of extern is not needed in function declarations or definitions. Its use is implicit. When extern is used with a variable, it’s only declared, not defined.

Can we declare extern inside a function?

An external variable may also be declared inside a function. In this case the extern keyword must be used, otherwise the compiler will consider it a definition of a local (automatic) variable, which has a different scope, lifetime and initial value.

Can you initialize an extern variable?

You can initialize any object with the extern storage class specifier at global scope in C or at namespace scope in C++. The initializer for an extern object must either: Appear as part of the definition and the initial value must be described by a constant expression; or.

What does extern mean?

variants: or less commonly externe. Definition of extern (Entry 2 of 2) : a person connected with an institution but not living or boarding in it specifically : a nonresident doctor or medical student at a hospital.

Can we initialize extern variable in C?

Here are some important points about extern keyword in C language, External variables can be declared number of times but defined only once. … Variables with “extern” keyword are only declared not defined. Initialization of extern variable is considered as the definition of the extern variable.

Which condition is true if extern variable is used in a file?

Which condition is true if the extern variable is used in a file? Explanation: Only one header file should declare the extern variable to be used. There must not be more than one file declaring the same extern variable. This is to ensure that there is no ambiguity in using the extern variable.

What is extern variable in C with example?

Extern is a keyword in C programming language which is used to declare a global variable that is a variable without any memory assigned to it. It is used to declare variables and functions in header files. Extern can be used access variables across C files.

What are the inherent danger of using external variable?

Using global variables causes namespace pollution. This may lead to unnecessarily reassigning a global value.

Which among the following is not applicable for static member function?

Which among the following is not applicable for the static member functions? Explanation: Since the static members are not property of objects, they doesn’t have this pointer. Every time the same member is referred from all the objects, hence use of this pointer is of no use.

What happens when new fails?

What happens when new fails? Explanation: While creating new objects, the new operator may fail because of memory errors or due to permissions. At that moment the new operator returns zero or it may throw an exception. The exception can be handled as usual.

What is the meaning of using extern before function declaration Mcq?

extern means nothing, sum() is same without extern keyword. Function need not to be declared before its use. Function is made local to the file. Explanation.

Which of the following is not a correct usage of keyword static?

4. Which of the following statements are incorrect? Explanation: All objects of class share same static variable, when object of a class are declared, all the objects share same copy of static members, no copy of static variables are made.

Which of the following Cannot be a friend in C++?

To explain I would say: Objects of any class cannot be made a friend of any other or same class whereas functions, classes and operator functions can be made a friend.

Which one of the following is not applicable for the C# keyword static?

static keyword cannot be used by indexers, finalizers, or types other than classes.

Which of the following Cannot be declared as static?

Discussion Forum
Que. Which of these cannot be declared static?
b. object
c. variable
d. method
Answer:object

Which of the following keywords are not allowed with local variable in Java?

The abstract keyword is not allowed with variables in Java. In short, only final is permitted with local variables in Java.

Can method be declared static?

Static methods

When a method is declared with the static keyword, it is known as the static method. The most common example of a static method is the main( ) method. As discussed above, Any static member can be accessed before any objects of its class are created, and without reference to any object.

Which of the following Cannot be declared as virtual?

Which of the following is selection statement in C++?
…
Q. Which of the following cannot be declared as virtual?
B. Destructor
C. Data Members
D. Both A and C
Answer» a. Constructor

Which of the component Cannot be declared as static in Java?

An inner class is by default not static, which is to say that each instance of a class that has a nested class gets its own copy of the nested class.