Golang Standard library Io/ioutil, read files, generate temporary directories/files

This is a creation in Article, where the information may have evolved or changed.

1. Reading the Directory

List, err: = Ioutil. ReadDir ("DIR")//to read the directory address dir, get the listifErr! =Nil {fmt. Println ("Read dir error")    return} for_, Info: = Range list {//traverse the contents of the directory, get the file details, with the OS. Information obtained by Stat (filename)Info. Name ()//file nameInfo. Mode ()//file PermissionsInfo. Size ()//File SizeInfo. Modtime ()//File modification TimeInfo. Sys ()//System Information    ifInfo. Isdir () = =true{fmt. Println ("is the directory")    }}

2. Reading files

Data, err: = Ioutil. ReadFile ("dir/filename")if err ! = nil {    FMT. Println ("read error")    return}fmt. Println (string(data))

3. Create a temp directory (OS. TempDir () returns the operating system's TEMP directory)

Dir, err: = Ioutil. TempDir ("dir""tmp"//In dir directory, create a directory with the TMP directory name prefix, Dir must exist, otherwise the creation is unsuccessful if err ! = nil {    FMT. Println (" temporary directory creation failed ")    return}fmt. Println (dir)  // generated directory named tmpxxxxx,xxxxx as a random number

4. Create a temporary file

File, Error: = Ioutil. Tempfile ("DIR","tmp")//create a file with the filename prefix in the dir directory, get the file pointer, dir must exist, or the creation will not succeeddefer file. Close ()ifError! =Nil {fmt. Println ("File creation failed")    return}file. WriteString ("INSERT INTO File")//write content with the WriteString () of the file pointer