The steps for reading from a file are:

Question

BlackTom AI · Accepted Answer

Files must be opened before operations can be performed on them, so the correct sequence when reading is: Open → Read → Close.

1) Relevant knowledge points and concepts
- File handles/resources: Operating systems require a file to be opened (which returns a handle or stream) before reading from it.
- Modes: Opening in a read mode (e.g., "r") grants read permissions; without opening, there is no valid stream.
- Cleanup: Closing releases system resources and ensures buffers and locks are properly handled.

2) Step-by-step reasoning process
Step 1 — Open: Request the OS to open the file in read mode. This yields a file handle/stream and performs checks (exists, permissions). If opening fails, you cannot proceed.
Step 2 — Read: Use the handle to read bytes/lines into memory. Multiple read calls may be used until EOF.
Step 3 — Close: When done, close the handle to free resources and flush/commit any internal state.

3) Intermediate steps (illustrative pseudocode)
- f = open("data.txt", "r")     # Open
- content = f.read()            # Read
- f.close()                     # Close

4) Why the correct answer is correct
Option c lists the logical and required order: Open first (to obtain a stream and permissions), then Read using that stream, then Close to release resources. This mirrors standard file I/O APIs in nearly all languages (C, Java, Python, etc.).

5) Why the other options are incorrect
- a. Write → Read → Close: Writing is not required for reading and may be disallowed if file opened for read-only; order is wrong.
- b. Open → Close → Read: Closing before reading invalidates the stream; reads will fail.
- d. Read → Open → Close: Reading before opening is impossible because no handle exists.

Conclusion
Following the OS and API requirements, the correct sequence is Open → Read → Close, so option c is correct, matching the provided answer.

The steps for reading from a file are:单项选择题

类似问题

Why is closing a file after writing important?

iii. Complete the code to open a file for reading and writing: file = open("data.txt", "Answer Question 30[input]")

Consider the following C code sequence: while (fread(&thing, sizeof(data_t), 1, fp) == 1) { // process item that was read ... } If this code sequence and function call appears in a program, it can be reasonably expected:

Which statement below can be used to read data from a file one character at a time?

In the code snippet below, if the file contains the following words: apple, pear, and banana stored one per line, what would be the output? infile = open("input.txt", "r") for word in infile : word = word.rstrip() print(word)

What is returned when the readline method reaches the end of the file?

Before accessing a file, the program must:

更多留学生实用工具

智能学习助手

风格化写作助手

论文查重助手

文献引用助手

课堂转译助手

课堂笔记助手

Quiz搜索助手

学校历年真题

智能刷题助手

智能匹配练习

希望你的学习变得更简单