Create a temporary file or directory

yourbasic.org/golang

File

Use ioutil.TempFile in package io/ioutil to create a globally unique temporary file. It’s your own job to remove the file when it’s no longer needed.

file, err := ioutil.TempFile("dir", "prefix")
if err != nil {
	log.Fatal(err)
}
defer os.Remove(file.Name())

fmt.Println(file.Name()) // For example "dir/prefix054003078"

The call to ioutil.TempFile

creates a new file with a name starting with "prefix" in the directory "dir",
opens the file for reading and writing,
and returns the new *os.File.

To put the new file in os.TempDir(), the default directory for temporary files, call ioutil.TempFile with an empty directory string.

Add a suffix to the temporary file nameGo 1.11

Starting with Go 1.11, if the second string given to TempFile includes a "*", the random string replaces this "*".

file, err := ioutil.TempFile("dir", "myname.*.bat")
if err != nil {
	log.Fatal(err)
}
defer os.Remove(file.Name())

fmt.Println(file.Name()) // For example "dir/myname.054003078.bat"

If no "*" is included the old behavior is retained, and the random digits are appended to the end.

Directory

Use ioutil.TempDir in package io/ioutil to create a globally unique temporary directory.

dir, err := ioutil.TempDir("dir", "prefix")
if err != nil {
	log.Fatal(err)
}
defer os.RemoveAll(dir)

The call to ioutil.TempDir

creates a new directory with a name starting with "prefix" in the directory "dir"
and returns the path of the new directory.

To put the new directory in os.TempDir(), the default directory for temporary files, call ioutil.TempDir with an empty directory string.