MCQs on File I/O | Lua
1. Reading from and Writing to Files
- Which function is used to open a file for reading in Lua?
- a)
io.read() - b)
io.open() - c)
io.write() - d)
file.open()
- a)
- How do you write data to a file in Lua?
- a)
io.write() - b)
io.append() - c)
io.input() - d)
file.write()
- a)
- What does the
io.read()function do in Lua?- a) It reads the entire content of a file
- b) It reads a specified number of characters from the file
- c) It opens a file for reading
- d) It writes data to the file
- Which of the following is used to read an entire file in Lua?
- a)
io.read("*all") - b)
io.read("*line") - c)
io.read("*char") - d)
io.read("*block")
- a)
- How can you close a file after reading or writing in Lua?
- a)
io.close() - b)
file.close() - c)
io.end() - d)
io.finish()
- a)
- Which function is used to write a string to a file in Lua?
- a)
io.write() - b)
io.print() - c)
io.output() - d)
file.write()
- a)
- When you open a file in write mode (
"w"), what happens if the file already exists?- a) It overwrites the file
- b) It appends data to the file
- c) It raises an error
- d) It creates a backup of the file
- How do you read a single line from a file in Lua?
- a)
io.read("*line") - b)
io.read(1) - c)
file.readline() - d)
io.read("*char")
- a)
- Which Lua function is used to read the next number from a file?
- a)
io.read("*number") - b)
io.read("*line") - c)
io.read("*all") - d)
file.read("*num")
- a)
- What happens if you attempt to write to a file that is not open for writing in Lua?
- a) An error is raised
- b) The data is written to the console
- c) The data is discarded
- d) The program crashes
2. Using io Library Functions
- Which function in the
iolibrary is used to open a file?- a)
io.open() - b)
io.file() - c)
io.openfile() - d)
file.open()
- a)
- Which of the following is a valid file mode for reading in Lua?
- a)
"r" - b)
"w" - c)
"a" - d)
"x"
- a)
- What file mode is used to open a file for appending in Lua?
- a)
"a" - b)
"r" - c)
"w" - d)
"rw"
- a)
- How do you open a file for both reading and writing in Lua?
- a)
"r+" - b)
"rw" - c)
"rw+" - d)
"r"
- a)
- Which function is used to check if a file exists in Lua?
- a)
io.open() - b)
io.check() - c)
io.exists() - d)
file.exists()
- a)
- What happens if a file is opened in
"r"mode but does not exist?- a) It returns
niland an error message - b) It creates a new file
- c) It raises a runtime error
- d) It creates a temporary file
- a) It returns
- How can you read multiple lines from a file in Lua?
- a) Using
io.read("*line")in a loop - b) Using
io.readlines() - c) Using
file.read("*lines") - d) Using
io.read(5)
- a) Using
- What is the purpose of the
io.flush()function in Lua?- a) It flushes the output buffer to the file
- b) It clears the content of a file
- c) It closes the file
- d) It reads the remaining content of the file
- What happens if you attempt to write to a file that was opened in
"r"mode?- a) An error is raised
- b) Data is written to the console
- c) The program ignores the write request
- d) The file is overwritten
- How can you write multiple lines to a file in Lua?
- a) Use
io.write()multiple times - b) Use
io.println() - c) Use
file.writelines() - d) Use
io.append()
- a) Use
3. Working with File Modes (Binary/Text)
- Which file mode in Lua is used for binary file reading?
- a)
"rb" - b)
"b" - c)
"rt" - d)
"w"
- a)
- How do you open a file for both reading and writing in binary mode?
- a)
"rb+" - b)
"rw+" - c)
"br+" - d)
"rw"
- a)
- What is the difference between the
"r"and"rb"modes in Lua?- a)
"r"opens a text file,"rb"opens a binary file - b)
"r"is used for writing,"rb"for reading - c)
"r"opens for reading and writing,"rb"for reading only - d) There is no difference
- a)
- What does the
"w"mode do when opening a file in Lua?- a) It opens the file for writing, creating a new file or overwriting an existing one
- b) It opens the file for writing, appending data
- c) It opens the file in binary mode
- d) It opens the file for reading
- What is the purpose of the
"a"mode when opening a file in Lua?- a) To open a file for appending data at the end of the file
- b) To open a file for reading and writing
- c) To open a file in binary mode
- d) To create a new file
- In Lua, which file mode is used for reading and writing with text encoding?
- a)
"r" - b)
"rb" - c)
"w" - d)
"wt"
- a)
- Which mode should be used to open a file for updating in Lua?
- a)
"r+" - b)
"w+" - c)
"rw" - d)
"b+"
- a)
- How can you open a file for writing, but only if the file does not already exist?
- a)
"x" - b)
"r+" - c)
"w" - d)
"a"
- a)
- What does
"rb"mode do when opening a file in Lua?- a) Opens the file for reading in binary mode
- b) Opens the file for reading in text mode
- c) Opens the file for writing in binary mode
- d) Opens the file for appending
- Which of the following modes can be used to append text to an existing file in Lua?
- a)
"a" - b)
"w" - c)
"r" - d)
"rb"
- a)
Answer Key
| Qno | Answer (Option with the text) |
|---|---|
| 1 | b) io.open() |
| 2 | a) io.write() |
| 3 | b) It reads a specified number of characters from the file |
| 4 | a) io.read("*all") |
| 5 | a) io.close() |
| 6 | a) io.write() |
| 7 | a) It overwrites the file |
| 8 | a) io.read("*line") |
| 9 | a) io.read("*number") |
| 10 | a) An error is raised |
| 11 | a) io.open() |
| 12 | a) "r" |
| 13 | a) "a" |
| 14 | a) "r+" |
| 15 | a) io.open() |
| 16 | a) It returns nil and an error message |
| 17 | a) Using io.read("*line") in a loop |
| 18 | a) It flushes the output buffer to the file |
| 19 | a) An error is raised |
| 20 | a) Use io.write() multiple times |
| 21 | a) "rb" |
| 22 | a) "rb+" |
| 23 | a) "r" opens a text file, "rb" opens a binary file |
| 24 | a) It opens the file for writing, creating a new file or overwriting an existing one |
| 25 | a) To open a file for appending data at the end of the file |
| 26 | a) "r" |
| 27 | a) "r+" |
| 28 | a) "x" |
| 29 | a) Opens the file for reading in binary mode |
| 30 | a) "a" |