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Example of Fscan, Fscanf, and Fscanln from FMT Package

Fscan scans text read from r, storing successive space-separated values into successive arguments.
Fscanf scans text read from r, storing successive space-separated values into successive arguments as determined by the format.
Fscanln is similar to Fscan, but stops scanning at a newline and after the final item there must be a newline or EOF.

To execute this program need to create a text file with name testfile.txt and content given in below program comment section.

Example

/* testfile.txt content:
255 5.5 true Australia
200 9.3 false Germany
Paris 5 true 5.5
*/
package main

import (
	"fmt"
	"os"
)

var (
	L int32
	M float32
	N bool
	O string
)

func main() {
	file, err := os.Open("testfile.txt")
	if err != nil {
		panic(err)
	}
	defer file.Close()
	
	fmt.Fscan(file, &L, &M, &N, &O)		
	fmt.Printf("\nL M N O: %v %v %v %v", L,M,N,O)
	
	fmt.Fscanln(file, &L, &M, &N, &O)
	fmt.Printf("\nL M N O: %v %v %v %v", L,M,N,O)
	
	fmt.Fscanf(file, "%s %d %t %f",&O, &L, &N, &M)
	fmt.Printf("\nO L N M: %v %v %v %v", O,L,N,M)
}

Output

L M N O: 255 5.5 true Australia
L M N O: 200 9.3 false Germany
O L N M: Paris 5 true 5.5
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