Golang: Read File

By Xah Lee. Date: . Last updated: .

Read Whole File

package main

import "fmt"
import "io/ioutil"

func main() {

	// read whole file
	myText, myErr := ioutil.ReadFile("/Users/x/filepath")

	if myErr != nil {
		panic(myErr)
		// panic means abort
	}

	// print it. String converts it to string
	fmt.Print(string(myText))

}

Read First X Bytes

package main

import "fmt"
import "os"

// open file. read first 200 bytes. print it.

var filePath = "/Users/xah/web/xahlee_info/golang/golang_read_file.html"

func getHeadBytes(path string, n int) []byte {

	file, err := os.Open(path) // For read access.
	if err != nil {
		panic(err)
	}

	defer file.Close()

	headBytes := make([]byte, n)
	m, err := file.Read(headBytes)
	if err != nil {
		panic(err)
	}

	return headBytes[:m]
}

func main() {

	fmt.Printf("%q\n", getHeadBytes(filePath, 200))

}

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