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

What is message passing libraries, Q. What is Message Passing Libraries? ...

Q. What is Message Passing Libraries? In this part we will consider about message passing libraries. Traditionally a range of message passing libraries have been available ever

Drawbacks, drawbacks of shadow paging

drawbacks of shadow paging

Determine the two input of NOR gate if output will be low, The NOR gate out...

The NOR gate output will be low if the two inputs are ? Ans. Output is low if any of the input is high means input may be 01,10 or 11.

What is normal form, What is normal form? A normal form is a guideline ...

What is normal form? A normal form is a guideline for relational database tables that enhances data consistency. As tables satisfy higher levels of normal forms, they are less

Bit serial associative processor (bsap), Bit Serial Associative Processor (...

Bit Serial Associative Processor (BSAP) : When the associative processor accepts bit serial memory organization then it is known as bit serial associative processor. While only one

Er diagrams, how can I draw er diagram for sell & storage section of a drug...

how can I draw er diagram for sell & storage section of a drugstore?

Data packet from one network to another, A device that forwards data packet...

A device that forwards data packet from one network to another is known as a  Switch device.

Android mobile application, Students are needed to work in group of 3 and m...

Students are needed to work in group of 3 and make an Android mobile application falling under the following categories: Multimedia o    Eg: Camera app, mp3 player, ga

Internal conditioning, types of internal conditioning with explanations and...

types of internal conditioning with explanations and examples

Explain traditional computer clusters, Q. Explain traditional computer clus...

Q. Explain traditional computer clusters? Grid computing employs resources of a lot of separate computers linked by a network (generally internet) to resolve large-scale comput

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