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# define pi 3.17 // tihs is a preprocessing directive macro.
"pi" is called macro template
" 3.17" is the macro value.
means in entire program pi value is 3.17.
if we declared like
# define pi 0
means pi value is zero means null.
so the macro template which carries a null value is called a NULL MACRO.
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∙ 13y ago
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What is a null macro what is the difference between a null pointer and a null macro?
NULL Macro is simply what is defined as 0 in a macro provided by the libraryNull pointer is a pointer which has 0 or NULL value stored and points to nowhwere still it points to 0x00 i.e. the first memory location of the OSNull pointer != Uninitialized pointer because an uninitialised pointer can point anywhere in the memory location ...but a NULL pointer surely points to no where(but still behind the scene we can say that it only points to 0x00). Never we can retrive a Null pointer location using th"&" operator..neither will malloc/calloc return NULL IF THERE IS SPACE IN THE MEMORY. NULL pointer is unique !!nishantnitb@aol.com
What is the difference between a null pointer and a null macro?
Using a NULL macro to make C portableI'll assume that you're asking your question for C type language programming. A NULL pointer is a pointer that's guarnteed to point to nothing. This may be 0 in a UNIX/Linux system or some other address in another system. Using the NULL macro to set/initialize your pointers will make your programs more portable among systems than using something like the 0.#include char *c = 0; // initialize to NULL--not portablechar *p = NULL; // initialize to NULL as defined in stdio is portableAddendumThe code:char *c = 0;actually is portable because the compiler converts 0's used in a pointer context (cast to a pointer) to the machine's representation of a NULL pointer, which may or may not be all 0 bits. The NULL macro itself might be defined as something like 0 or (void *)0, and both definitions are portable. As a corollary, the following code is also portable:if (!c) {// do something}because it is equivalent to:if (c != 0) {// do something}and the 0 above is converted to a NULL pointer because it is being compared with a pointer.
What is null macro?
The NULL macro is an implementation-defined macro. It is used to symbolise the zero address (0x0) in C programs and older C++ programs. It is not type safe, but is the conventional method of assigning the zero address to a pointer variable. C++11 introduced the type-safe nullptr data type.
Null in programming?
in Russian Null means zero. in some languages Null is a macro for zero. in others Null is a single-tone object which referes to the value Null and thus could be compared to other values. Null has many names from nill Nill nil in diffrent languages. most of the time, Null is used to indicate, no value is set to a variable.
Null Null Null?
Very small.
If null is compared with null what is the result-true or false or null or unknown?
You mean SQL? NULL = anything IS NULL NULL <> anything IS NULL ... NULL IS NULL = TRUE NULL IS NOT NULL = FALSE
What is the difference between executing a macro and calling a macro?
Calling a macro loads the macro into memory, while executing the macro runs the macro.
How do you get to the null in supersecret?
There is no null, it is just what it says when you log out. There is a null.
What is macro call?
Nested macro calls refer to the macro calls within the macros. A macros is available within other macro definitions also. In the scenario when a macro call occurs, which contains another macro call, the macro processor generates the nested macro definition as text and places it on the input stack. The definition of the macro is then scanned and the macro processor complies it.
What is nested macro calls?
Nested macro calls refer to the macro calls within the macros. A macros is available within other macro definitions also. In the scenario when a macro call occurs, which contains another macro call, the macro processor generates the nested macro definition as text and places it on the input stack. The definition of the macro is then scanned and the macro processor complies it.
What is is null?
main(){ char str[5]="hello"; if(str==NULL) printf("string null"); else printf("string not null"); }
What is the subset of null set?
The null set. Every set is a subset of itself and so the null set is a subset of the null set.
