Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
Summarize the distinction between an external variable definition and an external variable declaration.
When we have ''declared'' a variable, we have meant that we have told the compiler about the variable; i.e. its type and its name, as well as allocated a memory cell for the variable (either locally or globally). This latter action of the compiler, allocation of storage, is more properly called the definition of the variable. The stricter definition of declaration is simply to describe information ''about'' the variable. For automatic and register variables, there is no difference between definition and declaration. The process of declaring an automatic or a register variable defines the variable name and allocates appropriate memory. However, for external variables, these two operations may occur independently. This is important because memory for a variable must be allocated only once, to ensure that access to the variable always refers to the same cell.
If an external variable is to be used in a file other than the one in which it is defined, a mechanism is needed to ''connect'' such a use with the uniquely defined external variable cell allocated for it. This process of connecting the references of the same external variable in different files, is called resolving the references.
External variables may be defined and declared with a declaration statement outside any function, with no storage class specifier. Such a declaration allocates memory for the variable. A declaration statement may also be used to simply declare a variable name with the extern storage class specifier at the beginning of the declaration. Such a declaration specifies that the variable is defined elsewhere, i.e. memory for this variable is allocated in another file. Thus, access to an external variable in a file other than the one in which it is defined is possible if it is declared with the keyword extern; no new memory is allocated. Such a declaration tells the compiler that the variable is defined elsewhere, and the code is compiled with the external variable left unresolved. The reference to the external variable is resolved during the linking process
The 68HC11F1 has two types of serial ports namely asynchronous (SCI) and synchronous (SPI). The most common form of communication device used in control is the SCI as this provides
Q. Explain Passing Parameters in General Memory? The parameters can be passed in the memory too. In such a technique name of the memory location is used as a parameter. The res
Explain adaptive routing. Adaptive routing defines the ability of a system, by which routes are characterised through their destination, to change the path that the route takes
How non-relocatable programs are different from relocatable programs? Non relocatable program: It is one that cannot be made to execute in any type of area of storage other t
Q. How to convert Binary to Octal and Hexadecimal? Rules for these conversions are simple. For converting binary to octal binary number is splitted in groups of three, that are
Q. Explain about Deadlock Avoidance? To prevent deadlocks two kinds of techniques are used: 1) Static prevention: It employs P and V operators in addition to Semaphores to
Design a model for object oriented development The model for object oriented development could be shown as in Figure. It could be classified as dynamic / static and physical /
Explain the role of World Wide Web in the field of e-commerce. In the 1990s, the arrival of the World Wide Web on the Internet had shown a turning point in e-commerce by givin
Discuss in detail the features, benefits and implementation of JIT inventory system. JIT - Just in Time inventory systems - meaning, origin, need for JIT, benefits, Use of JIT
Calculating Block Size: B A unit of associatively -one tag for B A words B T unit of transfer-B T words to/from primary memory as a unit One valid bit for
Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd