Home / C Programming / Input / Output :: General Questions

C Programming :: Input / Output

  1. Point out the error in the program?

    #include 
    #include 
    
     int main() 
     {     
       unsigned char;   
       FILE *fp;   
       fp=fopen("trial", "r");  
       if(!fp)     
       {       
          printf("Unable to open file");          
          exit(1);    
      }    
      fclose(fp);    
      return 0;
     } 

     

     

  2. A.

    Error: in unsigned char statement

    B.

    Error: unknown file pointer

    C.

    No error

    D.

    None of above


  3. In a file contains the line "I am a boy\r\n" then on reading this line into the array str using fgets(). What will str contain?

  4. A.
    "I am a boy\r\n\0"
    B.
    "I am a boy\r\0"
    C.
    "I am a boy\n\0"
    D.
    "I am a boy"

  5. What is the purpose of "rb" in fopen() function used below in the code?

     FILE *fp;
     fp = fopen("source.txt", "rb"); 
    

  6. A.

    open "source.txt" in binary mode for reading

    B.

    open "source.txt" in binary mode for reading and writing

    C.

    Create a new file "source.txt" for reading and writing

    D.

    None of above


  7. What does fp point to in the program ?

    #include 
     int main() 
     {   
       FILE *fp;   
       fp=fopen("trial", "r");   
       return 0; 
     } 

     

  8. A.

    The first character in the file

    B.

    A structure which contains a char pointer which points to the first character of a file.

    C.

    The name of the file.

    D.

    The last character in the file.


  9. Which of the following operations can be performed on the file "NOTES.TXT" using the below code?

     FILE *fp;
     fp = fopen("NOTES.TXT", "r+"); 
    

  10. A.

    Reading

    B.

    Writing

    C.

    Appending

    D.

    Read and Write


  11. To print out a and b given below, which of the following printf() statement will you use?

    #include 
    
     float a=3.14;
     double b=3.14; 

     

  12. A.

    printf("%f %lf", a, b);

    B.

    printf("%Lf %f", a, b);

    C.

    printf("%Lf %Lf", a, b);

    D.

    printf("%f %Lf", a, b);


  13. Which files will get closed through the fclose() in the following program?

    #include 
     int main() 
     {   
       FILE *fs, *ft, *fp;  
       fp = fopen("A.C", "r");
       fs = fopen("B.C", "r");  
       ft = fopen("C.C", "r");    
       fclose(fp, fs, ft);     
       return 0; 
     } 
    

  14. A.

    "A.C" "B.C" "C.C"

    B.

    "B.C" "C.C"

    C.

    "A.C"

    D.

    Error in fclose()


  15. On executing the below program what will be the contents of 'target.txt' file if the source file contains a line "To err is human"?

    
     #include  int main()
     {     
       int i, fss;
       char ch, source[20] = "source.txt", target[20]="target.txt", t;  
       FILE *fs, *ft;    
       fs = fopen(source, "r");   
       ft = fopen(target, "w");   
       while(1)     
       {
             ch=getc(fs);       
             if(ch==EOF)        
                  break;     
             else        
            {          
               fseek(fs, 4L, SEEK_CUR);                   
               fputc(ch, ft);      
            }    
       }     
       return 0; 
    }

     

  16. A.

    r n

    B.

    Trh

    C.

    err

    D.

    None of above


  17. To scan a and b given below, which of the following scanf() statement will you use?

    #include 
     float a; 
     double b; 
    

  18. A.

    scanf("%f %f", &a, &b);

    B.

    scanf("%Lf %Lf", &a, &b);

    C.

    scanf("%f %Lf", &a, &b);

    D.

    scanf("%f %lf", &a, &b);


  19. Out of fgets() and gets() which function is safe to use?

  20. A.
    gets()
    B.
    fgets()