Go Program Code

package main

import (
    "bufio"
    "fmt"
    "os"
)

func main() {
    // Specify the file name to read from
    fileName := "example.txt"

    // Open the file
    file, err := os.Open(fileName)
    if err != nil {
        fmt.Println("Error opening file:", err)
        return
    }
    defer file.Close()

    // Create a scanner to read the file line by line
    scanner := bufio.NewScanner(file)
    
    // Read each line from the file and print it
    fmt.Println("Contents of the file:")
    for scanner.Scan() {
        fmt.Println(scanner.Text())
    }

    // Check if there was an error reading the file
    if err := scanner.Err(); err != nil {
        fmt.Println("Error reading file:", err)
    }
}
        

Program Explanation

The program above reads the contents of a file and prints each line on the console.

Code Breakdown:

• import: We import three necessary packages:
  • bufio: To create a scanner that reads the file line by line.
  • fmt: For printing output to the console.
  • os: To open and handle the file operations.
• fileName: This variable holds the name of the file we want to read. In this case, it’s “example.txt”.
• os.Open(fileName): This function is used to open the file. If an error occurs (like if the file does not exist), it prints the error message and terminates the program.
• defer file.Close(): This ensures that the file is closed when the program finishes execution, even if an error occurs.
• bufio.NewScanner(file): This scanner allows us to read the file line by line, making it easy to process large files.
• scanner.Scan(): This method reads the next line of the file. The loop continues as long as there are lines to read.
• scanner.Text(): This method retrieves the text of the current line, which is then printed to the console.
• scanner.Err(): This checks for any errors that might have occurred during reading the file.

How to Run the Program

1. 1. Make sure you have Go installed on your system. You can download Go from the official website: Go Downloads.
   2. Create a new text file (e.g., example.txt) and add some content to it. Place this file in the same directory as your Go program.
   3. Write the Go program provided above in a file, say readfile.go.
   4. Open a terminal/command prompt, navigate to the directory where your Go program is located, and run the following command to execute the program:

go run readfile.go

1. The program will open the example.txt file, read its contents, and display them on the console.