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

Discuss the advantages of store program control, Discuss the advantages of ...

Discuss the advantages of store program control (SPC) automation in telephone switching. Advantages of SPC: (i) Simple to control (ii) Simple to maintain (iii) Fine-

What is vertical organization and horizontal organization, What is vertical...

What is vertical organization and horizontal organization? Highly encoded schemes that use compact codes to state only a small number of control functions in every microinstruc

Why echo suppressor is detrimental to full duplex operation, Echo suppresso...

Echo suppressor is detrimental to full duplex operation because? This disables one of the two pairs in a four-wire trunk line while a signal is detected upon another pair.

Drawbacks to having call centres overseas, Drawbacks to having call centres...

Drawbacks to having call centres overseas -  Culture and language problems -  Animosity to overseas call centres (resulting in loss of customers) -  need for extensive r

Explain busy hour call attempts in telephone traffic, With reference to tel...

With reference to telephone traffic, explain the terms BHCA. BHCA: The number of call attempts in the busy hour is termed as busy hour call attempts (BHCA) that is an importa

Pc configuration and troubleshooting, You have been asked to become the con...

You have been asked to become the consulting technician for MobTex, a local auto servicing centre. The general manager (Jo) realises that the IT system has evolved over time with l

Signals and systems, Im doing computer engineering in Thailand.. Second yea...

Im doing computer engineering in Thailand.. Second year, and got project regarding sysnal and systems.. I and my team mates have no idea on what should we do.. Could u kindly sugge

Explain working of telnet, Q. Explain Working of TELNET? The working o...

Q. Explain Working of TELNET? The working of TELNET 1.  Commands and characters are sent to operating system on common server computer. 2.  Local operating system send

Difference between narrative form and documentary form, Question: (a) E...

Question: (a) Explain clearly the difference between a Proposal and a Treatment for a video production project. (b) Explain clearly the difference between Narrative form an

Computer Fundamentals, state and explain the advantages of having densely ...

state and explain the advantages of having densely packed integrated Circuits in the computer

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