File Processing

1. Which Python function is used to open a file for reading ?
   1. open("file.txt", "w")
   2. open("file.txt", "r")
   3. read("file.txt")
   4. write("file.txt", "r")
   Show Answer

   Answer : B
   Explain : open("filename", "mode") here file.txt is file nama and r is read mode.
2. Which method is used to read the entire content of a file as a single string ?
   1. read()
   2. readline()
   3. readlines()
   4. readall()
   Show Answer

   Answer : A
   Explain : read() function is used to read entire data in a file. readline() is used to read line by line. The readlines() method in Python is used for reading all lines from a file and returning them as a list of strings.
3. What is the purpose of the "w" mode when opening a file ?
   1. Read mode
   2. Write mode
   3. append mode
   4. Binary mode
   Show Answer

   Answer : B
   Explain : w mode is used for write text file.
4. Fill in the blank :

   import pickle
   f=open("data.dat", "rb")
   d=_______.load(f)
   f.close()
   

   1. unpickle
   2. pickling
   3. pickle
   4. pick
   Show Answer

   Answer : C
   Explain : pickle is used before .load(filename).
5. Which mode should be used when opening a file for both reading and writing ?
   1. "r"
   2. "w"
   3. "a"
   4. "rw"
   Show Answer

   Answer : D
   Explain : rw is used for read and write.
6. What is the purpose of the seek() method in file handling ?
   1. It moves the file pointer to a specified position.
   2. It opens a file in read mode.
   3. It appends content to the end of the file.
   4. It closes the file.
   Show Answer

   Answer : A
   Explain : seek () change and modify the position of pointer.
7. Which method is used to write a list of strings to a file ?
   1. write_list()
   2. writelines()
   3. write_lines()
   4. appendlines()
   Show Answer

   Answer : B
   Explain : writelines() is used to write the sequence of string to a file.
8. What happens if you try to open a file using the "w" mode that does not exist ?
   1. The file will be created if it doesn't exist.
   2. An error will occur since the file must already exist.
   3. The file will be opened in read mode automatically.
   4. The program will wait until the file is created.
   Show Answer

   Answer : A
   Explain : "w" the file will create if not created.
9. Which function should be used to check if a file exists before trying to open it ?
   1. check_file_exists()
   2. file_exists()
   3. os.path.exists()
   4. isfile()
   Show Answer

   Answer : C
   Explain : exists() method is used to check whether the given path points to an existing file or directory or not. It returns boolean value if exist true, if not then false.
10. which statement will return one line from a file (file object is ‘f’) ?
    1. f.readline()
    2. f.readlines()
    3. f.read()
    4. f.line()
    Show Answer

    Answer : A
    Explain : readline() is used to read line by line.
11. Which of the following function takes two arguments ?
    1. load()
    2. dump()
    3. both of above
    4. None of the above
    Show Answer

    Answer : B
    Explain : Note that dump() takes two positional arguments: (1) the data object to be serialized, and (2) the file-like object to which the bytes will be written.
12. Which mode creates a new file if the file does not exist ?
    1. write mode
    2. append mode
    3. both
    4. None
    Show Answer

    Answer : C
    Explain : Both write mode and append mode creates file if not exist.
13. which statement will read 5 characters from a file ?
    1. f.read()
    2. f.read(5)
    3. f.reads(5)
    4. None of above
    Show Answer

    Answer : B
    Explain : f.read(5) only read 5 characters of file.
14. which is the function to read the remaining lines of the file from a file object 'infile' ?
    1. infile.read(2)
    2. infile.read()
    3. infile.readlines()
    4. infile.readline()
    Show Answer

    Answer : B
    Explain : read() is used to read the entire data in a file.
15. What will be the output of following code ?

    f = open("demo.txt","r")
    print(f.tell())
    f.close()
    

    1. 1
    2. 2
    3. -1
    4. 0
    Show Answer

    Answer : D
    Explain : tell() is used to tell the curent position of pointer. When we open the curent position is at starting which is 0.