#1
Which keyword is used to define a macro in C?
#define
ExplanationDefines a macro.
#2
What does the preprocessor directive #include do in C?
Includes the standard input/output functions
ExplanationIncludes standard input/output functions.
#3
What is the purpose of the ## operator in C macro definitions?
Concatenates two tokens
ExplanationConcatenates two tokens.
#4
In C, what is the significance of the #undef directive?
Undefines a macro
ExplanationUndefines a macro.
#5
What is the purpose of the #ifdef preprocessor directive in C?
Checks if a macro is defined
ExplanationChecks if a macro is defined.
#6
How can you concatenate two strings in a C macro?
Using the ## operator
ExplanationUsing the ## operator to concatenate strings.
#7
Which preprocessor directive is used for conditional compilation in C?
#if
ExplanationUsed for conditional compilation.
#8
What is the purpose of the #pragma once directive in C?
Ensures that the header file is only included once
ExplanationEnsures the header file is only included once.
#9
What does the ## operator do in C macro definitions?
Concatenates adjacent tokens
ExplanationConcatenates adjacent tokens.
#10
In C, what is the role of the __LINE__ macro?
Returns the current line number
ExplanationReturns the current line number.
#11
How can you check if a macro is defined or not in C?
#ifdef
ExplanationCheck if a macro is defined.
#12
How is the #if directive different from the #ifdef directive in C?
#if checks for macro equality, #ifdef checks for macro existence
Explanation#if checks for macro equality, #ifdef checks for macro existence.
#13
In C, what is the purpose of the #pragma region directive?
Defines a code region for folding in the editor
ExplanationDefines a code region for folding in the editor.
#14
What is the purpose of the __TIME__ macro in C?
Returns the current time
ExplanationReturns the current time.
#15
Which of the following is true about function-like macros in C?
They can have parameters
ExplanationFunction-like macros can have parameters.
#16
What is the purpose of the # operator in a C macro?
Indirectly references a variable
ExplanationIndirectly references a variable.
#17
In C, what is the role of the #pragma directive?
Specifies compiler-specific instructions
ExplanationSpecifies compiler-specific instructions.
#18
What is the purpose of the __FILE__ macro in C?
Returns the current file name
ExplanationReturns the current file name.
#19
What is the purpose of the #error directive in C?
Outputs an error message during compilation
ExplanationOutputs an error message during compilation.
#20
How are inline functions different from function-like macros in C?
Inline functions are defined using the #define directive
ExplanationInline functions are defined using the #define directive.
#21
Which of the following is true about recursive macros in C?
They can result in infinite recursion
ExplanationThey can result in infinite recursion.
#22
What is the purpose of the #pragma message directive in C?
Specifies a compiler-specific message
ExplanationSpecifies a compiler-specific message.
#23
What is the purpose of the #pragma pack directive in C?
Specifies packing alignment for structures
ExplanationSpecifies packing alignment for structures.
#24
Which directive is used to include a file in C multiple times?
#ifndef
ExplanationUsed to include a file multiple times.
#25
What is the purpose of the #pragma startup directive in C?
Specifies the entry point for the program
ExplanationSpecifies the entry point for the program.