what is the disadvantage of using macros?
Though, macro has advantages... it hav few disadvantages
too...
------------------------------------------------------------
1.1st disadvantage is, In debugging time u can't see the
value of the macro assigned to it.
So, u have to have ur source file, to fine out the value of
the macro.
But nowadays there are some debuggers which are capable of
showing the value of macro in debugging time.
------------------------------------------------------------
2.Dont use macro for typedef or be cautious before use.
Ex:
lets say, u wanted to have a macro, which can be used to
represent a declaration to an int pointer
#define INTPTR int*
in main..
main()
{
INTPTR a, p;
/*here, our understanding will be 'a' and 'p' both are int
pointers*/
}
but in preprocessor time macro shall be replaced like this -
> int* a, p;
so only 'a' will be treated as int pointer and 'p' shall a
normal int variable.
So tyr to avoid using MACRO for typedef.
use -> typedef int* INTPTR, So that u can achieve desired
result.
------------------------------------------------------------
3.Be carefull while using macro in arithmatic operation.
Ex:
#define MUL(a,b) a*b
In main...
main()
{
int a = 3, b = 4;
....
....
.....
printf("%d", MUL(a+1, b+1));
/*Here u may expect the result 4 * 5 = 20 but the result
would be 8*/
}
lets analise,
in preprocessing time macro shall be replaced as below;
MUL(a+1, b+1) - > 3+1*4+1, so result would be 8.
To avoid the unexpected result.
Define macro lik ...
#define MUL(a,b) (a)*(b)
------------------------------------------------------------
| Is This Answer Correct ? | 5 Yes | 3 No |
Write a program to reverse a string.
0 Answers Global Logic, iNautix, TCS, Wipro,
what would be the output of the following program? main() { int k = 123; char *ptr; ptr = &k; printf("%d",*ptr); }
Define a structure to store the record of library. The record must consist of at least following fields: Title, Author, Edition, Price, Publisher, and Category. -Define functions authorSearch ( ), TitleSearch ( ) and CategorySearch ( ) to search a book with respect to author, title and category. [There can be more than one book, written by one author, in one category]
What's the difference between struct x1 { ... }; and typedef struct { ... } x2; ?
What is the advantage of c?
What is undefined behavior?
Why is c faster?
Given a valid 24 hour format time find the combination of the value and write a program ,do not hard the value and if any other inputs provided should work with the logic implemented Input: 11:30 Output: 13:10 Input: 18:25 Output: 21:58
What is the o/p of the follow pgm? #include<stdio.h> main() { char char_arr[5]=”ORACL”; char c=’E’; prinf(“%s\n”,strcat(char_arr,c)); } a:oracle b. oracl c.e d.none
what is compiler
What is NULL pointer?
Explain do array subscripts always start with zero?