Go (golang) Tutorials - File I/O using OS Package

#golang #go #input #output #file File I/O - OS Package ---------- = Writing a []byte to a file = Writing a string to a file = Read []byte from a file = Seek = Read a set of bytes from a file filedemo.go ----------- package main import "os" func main(){ file,err:=os.Create("myfile") //Create a new file myfile if err!=nil { panic(err) } data:=[]byte("Hello world\n") file.Write(data) //Data as a byte array file.WriteString("This is a String\n") //Write data as a string file.Close() } readdemo.go ----------- package main import ( "fmt" "os" ) func main(){ file,err:=os.Open("myfile") if err!=nil { panic(err) } data:=make([]byte,5) //The data read from the file will be of the size of the byte array file.Seek(6,0) //I want to seek the file pointer to the 5th byte of the data //Seek has two arguments, first one is the position of file pointer to read data //From where in the file to read from, 0 - beginning, 1-at current position, 2-from end file.Read(data) //read the data from file to the byte array 'data' //fmt.Printf("The file data is %s\n",string(data)) fmt.Println(string(data)) file.Seek(0,0) newdata:=make([]byte,5) file.Read(newdata) fmt.Println(string(newdata)) file.Close() }