Standard Library Functions MCQ

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• The abs() function computes the absolute value . . . . . . . .
  ক

  a floating number

  খ

  an integer number

  গ

  a double number

  ঘ

  all of the mentioned
• The macro . . . . . . . . defines the number of bits in a byte, which is equal to . . . . . . . .
  ক

  CHAR_BIT, 4

  খ

  CHAR_BYTE, 8

  গ

  CHAR_BIT, 8

  ঘ

  CHAR_BYTE, 4
• If setjmp() macro returns directly from the macro invocation, it . . . . . . . .
  ক

  returns zero

  খ

  returns non-zero

  গ

  produces error

  ঘ

  nothing can be said
• The void longjmp( jmp-buf env, int val) function causes setjmp() macro to return . . . . . . . . value; if val is 0.
  ক

  zero

  খ

  one

  গ

  null

  ঘ

  no return
• Point out the error (if any) in the following C code?<br><pre><code class="c-program">#include &lt;stdlib.h&gt;#include &lt;stdio.h&gt;int main(void){ int* p = NULL; struct S *s = NULL; void(*f)(int, double) = NULL; char *ptr = malloc(15); if (ptr == NULL) printf("Out of memory"); free(ptr);}</code></pre>
  ক

  Error in the statement: void(*f)(int, double) = NULL;

  খ

  Error in the statement: char *ptr = malloc(15);

  গ

  Error in the statement: struct S*s = NULL;

  ঘ

  No error
• . . . . . . . . macro must be called before using . . . . . . . . and . . . . . . . .
  ক

  va_arg, va_end and va_start

  খ

  va_start, va_end and va_arg

  গ

  va_end, va_arg and va_start

  ঘ

  v_arg, v_end and v_start
• The three macros defined by stdarg.h is . . . . . . . .
  ক

  start(), arg() and end()

  খ

  var_start(), var_arg() and var_end()

  গ

  va_start(), va_arg() and va_end()

  ঘ

  v_start(), v_arg() and v_end()
• The value of tm_isdst is . . . . . . . . when DST( Daylight Savings Time) is in effect, . . . . . . . . when DST is not in effect and . . . . . . . . when the DST status is unknown.
  ক

  -1, 1, 0

  খ

  1, 0, -1

  গ

  0, 1, -1

  ঘ

  1, -1, 0
• Initial seed is . . . . . . . . for the function srand(unsigned int seed).
  ক

  0

  খ

  1

  গ

  00

  ঘ

  01
• Which of the following statement is correct?<br><pre><code class="c-program">double x, y, z;x = 5.123456;z= modf(x, *y);</code></pre>
  ক

  y stores integer part of x, z returns fractional part of x

  খ

  y stores integer part of x, z returns integer part of x

  গ

  y stores fractional part of x, z returns integer part of x

  ঘ

  y stores fractional part of x, z returns fractional part of x
• Is this right explanation to the given code?<br><pre><code class="c-program">void *calloc(size_t n, size_t size) #n -- This is the number of elements to be allocated.#size -- This is the size of elements.</code></pre>
  ক

  true

  খ

  false
• If the result overflows, the function returns the value of the macro HUGE_VAL, carrying the same sign except for the . . . . . . . . function as the correct value of the function.
  ক

  sin

  খ

  cos

  গ

  cosec

  ঘ

  tan
• The . . . . . . . . function returns no value.
  ক

  malloc()

  খ

  realloc()

  গ

  free()

  ঘ

  calloc()
• The system() function passes the string pointed to by string to the host environment to be executed by a command processor in an implementation-defined manner.<br><pre><code class="c-program">int system(const char *string);</code></pre>
  ক

  true

  খ

  false
• The . . . . . . . . function sorts an array of objects.
  ক

  bsort()

  খ

  hsort()

  গ

  ssort()

  ঘ

  qsort()
• When we use multiple alignas specifiers in the same declaration, the . . . . . . . . one is used.
  ক

  first

  খ

  strictest

  গ

  last

  ঘ

  middle
• What will the following C statement do?<br><pre><code class="c-program">#include &lt; setjmp.h &gt;int setjmp(jmp_buf env);</code></pre>
  ক

  save the current state of the registers into env

  খ

  resets the registers to the values saved in env

  গ

  provides a definition for env structure

  ঘ

  accept variable(env) argument lists to be written
• If NDEBUG is defined as a macro name, at the point where &lt;assert.h&gt; is included, then assert macro is defined as #define assert(ignore) ((void)0).
  ক

  true

  খ

  false
• The assert macro returns . . . . . . . . value.
  ক

  integer

  খ

  float

  গ

  double

  ঘ

  no
• If access to the varying arguments is desired then the called function shall declare . . . . . . . . having type va_list.
  ক

  class

  খ

  object

  গ

  function

  ঘ

  variable
• The value of CHAR_MAX will be equal to SCHAR_MAX when . . . . . . . .
  ক

  char represents positive value

  খ

  char represents value equal to 0

  গ

  char represents negative value

  ঘ

  char represents an exponential value
• The purpose of the function ctime() is that . . . . . . . .
  ক

  it returns a string representing the local time

  খ

  it returns a void string

  গ

  it returns a string representing the time in UTC format

  ঘ

  it returns a string representing the time stored in a structure
• HUGE_VAL macro is used when the output of the function may not be . . . . . . . .
  ক

  floating point numbers

  খ

  integer number

  গ

  short int

  ঘ

  long int
• The value returned by the library function mktime(), on failure is . . . . . . . .
  ক

  -1

  খ

  0

  গ

  1

  ঘ

  -2
• What is the purpose of the given C code?<br><pre><code class="c-program">#include &lt;stdlib.h&gt; _Mbsave _Mbxtowc = {0}; int (mbtowc) (wchar_t *pwc, const char *a, size_t n) {return (-Mbtowc (pwc, s, n, &amp;-Mbxtowc) ) ;}</code></pre>
  ক

  determine length of next multibyte code

  খ

  translates multibyte character to wide character

  গ

  translate multibyte string to wide char string

  ঘ

  translate wide character to multibyte string
• What is the meaning of the following C code if output is 0?<br><pre><code class="c-program">#include&lt;stdio.h&gt;#include&lt;time.h&gt;int main(){ struct tm *local; time_t t; t=time(NULL); local=localtime(&amp;t); printf("%d",local-&gt;tm_isdst); return 0;}</code></pre>
  ক

  DST is in effect

  খ

  DST status is unknown

  গ

  DST is not in effect

  ঘ

  DST is corresponding with local time
• void free(void *ptr) deallocates the memory previously allocated by a call to . . . . . . . . , . . . . . . . . or . . . . . . . .
  ক

  malloc,getenv,abort

  খ

  calloc,malloc,exit

  গ

  calloc,malloc,realloc

  ঘ

  exit,getenv,abort
• To find the maximum value of an object of type unsigned long long int, we use the macro . . . . . . . .
  ক

  ULINT_MAX

  খ

  ULLINT_MAX

  গ

  ULONG_MAX

  ঘ

  ULLONG_MAX
• What is "a" in the given C code?<br><pre><code class="c-program">size_t wcstombs(char *s, const wchar_t *a, size_t n)</code></pre>
  ক

  "a" is wide character string to be converted

  খ

  "a" is pointer to an array of char elements

  গ

  "a" is pointer to the first byte of a multi-byte character

  ঘ

  "a" C multibyte character string to be interpreted
• The assert shall be implemented as a . . . . . . . . not as an actual . . . . . . . .
  ক

  function, macro

  খ

  macro, function

  গ

  header, macro

  ঘ

  macro, header