C Preprocessor MCQ

Test your knowledge with important C Preprocessor MCQ and their applications. These MCQs are beneficial for competitive exams too. Explore 30 + more C Preprocessor MCQs at Bissoy

• The correct syntax of the attribute packed is . . . . . . . .
  ক

  __attribute__((packed));

  খ

  _attribute(packed);

  গ

  _attribute_((packed));

  ঘ

  __attribute__(packed);
• The pragma . . . . . . . . is used to remove an identifier completely from a program.
  ক

  GNU piston

  খ

  GCC poison

  গ

  GNU poison

  ঘ

  GCC piston
• The purpose of the preprocessor directive #error is that . . . . . . . .
  ক

  It rectifies any error present in the code

  খ

  It rectifies only the first error which occurs in the code

  গ

  It causes the preprocessor to report a fatal error

  ঘ

  It causes the preprocessor to ignore an error
• The preprocessor directive which checks whether a constant expression results in a zero or non-zero value . . . . . . . .
  ক

  #if

  খ

  #ifdef

  গ

  #undef

  ঘ

  #ifndef
• The function of __attribute__((packed)); can also be performed using . . . . . . . .
  ক

  #pragma pack(1);

  খ

  #pragma pack(2);

  গ

  #pragma pack(4);

  ঘ

  #pragma pack(8);
• #pragma GCC poison should be followed by a list of identifiers that are . . . . . . . .
  ক

  even in number

  খ

  odd in number

  গ

  valid

  ঘ

  invalid
• The preprocessor directive used to give additional information to the compiler, beyond which is conveyed in the language . . . . . . . .
  ক

  #include

  খ

  #define

  গ

  #pragma

  ঘ

  #elif
• The following C code results in an error.<br><pre><code class="c-program">#include &lt;stdio.h&gt;#define world( n ) printf( "t^^" #n" = %c", t##n )int t3=1;int main(){ world(3);}</code></pre>
  ক

  True

  খ

  False
• In the directive #pragma pack(n), if the value of 'n' is given to be 5, then what happens?
  ক

  Error

  খ

  Warning but no error

  গ

  Executes the pragma statement

  ঘ

  Ignores the pragma statement and executes the program
• . . . . . . . . is the preprocessor directive which is used to end the scope of #ifdef.
  ক

  #elif

  খ

  #ifndef

  গ

  #endif

  ঘ

  #if
• Find the output of the following program.<br><pre><code class="c-program">#define INC(X) X++void main(){ int x=4; printf("%d", INC(x++));}</code></pre>
  ক

  4

  খ

  5

  গ

  6

  ঘ

  Error
• The output of the following program is:<br><pre><code class="c-program">#define f(g,g2) g##g2void main(){ int var12=100; printf("%d", f(var,12));}</code></pre>
  ক

  Syntax error

  খ

  Runtime error

  গ

  g##g2

  ঘ

  100

  ঙ

  10012
• What will be output after executing following code?<br><pre><code class="c-program">#include&lt;stdio.h&gt;# define a 10void main(){ printf("%d..", a); foo(); printf("%d", a);}void foo(){ #undef a #define a 50}</code></pre>
  ক

  10..50

  খ

  10..10

  গ

  0

  ঘ

  Error
• What will be output if you will compile and execute the following c code?<br><pre><code class="c-program">#include&lt;stdio.h&gt;#define max 5void main(){ int i = 0; i = max++; printf("%d", i++);}</code></pre>
  ক

  5

  খ

  6

  গ

  7

  ঘ

  0

  ঙ

  Compiler Error
• Choose the correct statement.<br>I.   The scope of a macro definition need not be the entire program.<br>II.  The scope of a macro definition extends from the point of definition to the end of the file.<br>III. New line is a macro definition delimiter.<br>IV.  A macro definition may go beyond a line.
  ক

  I and II

  খ

  II and III

  গ

  I, II and III

  ঘ

  II, III and IV

  ঙ

  I, II, III and IV
• A preprocessor command
  ক

  need not start on a new line

  খ

  need not start on the first column

  গ

  has # as the first character

  ঘ

  comes before the first executable statement
• C preprocessor
  ক

  Takes care of conditional compilation

  খ

  Takes care of macros

  গ

  Takes care of include files

  ঘ

  Acts before compilation

  ঙ

  All of the above
• In C, what is the purpose of the #line directive?
  ক

  Specifies the line number and filename in the source file

  খ

  Defines a macro

  গ

  Checks for syntax errors

  ঘ

  Excludes code
• What is the result of the #pragma warning directive in C preprocessing?
  ক

  Generates a warning message

  খ

  Defines a macro

  গ

  Checks for syntax errors

  ঘ

  Excludes code
• In C preprocessing, what is the purpose of the #elifndef directive?
  ক

  Checks if a macro is defined

  খ

  Checks if a macro is not defined

  গ

  Provides an alternative condition

  ঘ

  Defines a macro
• What is the purpose of the #undef directive in C preprocessing?
  ক

  Undefines a macro

  খ

  Defines a macro

  গ

  Checks for syntax errors

  ঘ

  Excludes code
• What is the result of the #pragma message directive in C preprocessing?
  ক

  Includes a message in the code

  খ

  Defines a macro

  গ

  Checks for syntax errors

  ঘ

  Excludes code
• In C preprocessing, what is the purpose of the #elifdef directive?
  ক

  Checks if a macro is defined

  খ

  Checks if a macro is not defined

  গ

  Provides an alternative condition

  ঘ

  Defines a macro
• What is the purpose of the #pragma warning directive in C preprocessing?
  ক

  Generates a warning message

  খ

  Defines a macro

  গ

  Checks for syntax errors

  ঘ

  Excludes code
• In C, what is the purpose of the #ifdef directive?
  ক

  Checks if a macro is defined

  খ

  Checks if a macro is not defined

  গ

  Defines a macro

  ঘ

  Includes a header file
• What does the #pragma once directive do in C preprocessing?
  ক

  Prevents multiple inclusion of header files

  খ

  Defines a macro

  গ

  Checks for syntax errors

  ঘ

  Excludes code
• In C, how do you use the #ifndef directive to conditionally include code if a macro is not defined?
  ক

  #ifndef MACRO

  খ

  #ifndef(MACRO)

  গ

  #ifndef:MACRO

  ঘ

  #ifndef: MACRO
• What is the purpose of the #pragma message directive in C preprocessing?
  ক

  Includes a message in the code

  খ

  Defines a macro

  গ

  Checks for syntax errors

  ঘ

  Excludes code
• What is the result of the #error directive in C preprocessing?
  ক

  Generates a compilation error with a specified error message

  খ

  Defines a macro

  গ

  Checks for syntax errors

  ঘ

  Excludes code
• In C preprocessing, what is the purpose of the #elif directive?
  ক

  Checks if a macro is defined

  খ

  Checks if a macro is not defined

  গ

  Provides an alternative condition

  ঘ

  Defines a macro