Defines a macro, Computer Engineering

Assignment Help:

Defines a macro

Defines a macro with the given name, having as its value the given replacement text. After that (for the rest of the current source file), wherever the preprocessor sees that name, it will replace it with the replacement text. The name follows the same rules as ordinary identifiers (it can contain only letters, digits, and underscores, and may not begin with a digit). Since macros behave quite differently from normal variables (or functions), it is customary to give them names which are all capital letters (or at least which begin with a capital letter). The replacement text can be absolutely anything--it's not restricted to numbers, or simple strings, or anything.

The most common use for macros is to propagate various constants around and to make them more self-documenting. We've been saying things like

char line[100];

...

getline(line, 100);

but this is neither readable nor reliable; it's not necessarily obvious what all those 100's scattered around the program are, and if we ever decide that 100 is too small for the size of the array to hold lines, we'll have to remember to change the number in two (or more) places.

A much better solution is to use a macro:

#define MAXLINE 100 char line[MAXLINE];

...

getline(line, MAXLINE);

 


Related Discussions:- Defines a macro

The pre-generated selection screen, With LDB one can change the pre-generat...

With LDB one can change the pre-generated selection screen to their needs Yes with LDB one can alter the pre-generated selection screen.

Distributed workstation cluster, A distributed workstation cluster must be ...

A distributed workstation cluster must be viewed like single computing resource and not as a group of particular workstations'.  Details of cluster were: 150MHz R4400 workstatio

Where the trunks lines are run, Trunks are the lines that run between? ...

Trunks are the lines that run between? Trunks are the lines which run in between switching stations.

Describe jmx concepts and architecture, MX is conceptually easy, yet bears ...

MX is conceptually easy, yet bears the fruit of years of domain experience and research. In a nutshell, JMX describes a standard means for applications to expose management functio

Telecommunications, with poisson arrival of two calls per minute what is th...

with poisson arrival of two calls per minute what is the probability that more than three calls will arrive in two minutes? that is the time during which at least 4 calls will arr

What is c language, The C programming language is a standardized programmin...

The C programming language is a standardized programming language forrned in the early 1970s by Ken Thompson and Dennis Ritchie for use on the UNIX operating system. It has since s

What are the major systems of a telecommunication network, What are the maj...

What are the major systems of a telecommunication network? The main systems of any telecommunication network may contain the following main systems: a. Subscriber end instr

I have a user defined function that does not recalculate, Contain all the c...

Contain all the cells that your UDF depends on in the argument list. Or enter this as the first statement in your Function: Application.Volatile This will cause the functi

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

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!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd