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The `filepath` package provides functions to parse and construct *file paths* in a way that is portable between operating systems; `dir/file` on Linux vs. `dir\file` on Windows, for example. 
package main
 






    
    
        
    

    






    
    
import (

    






    
    
	"fmt"

    






    
    
	"path/filepath"

    






    
    
	"strings"

    






    
    
)

    






    
    
        
    

    






    
    
func main() {

    






    
    
        
    

    






    
    
         `Join` should be used to construct paths in a portable way. It takes any number of arguments and constructs a hierarchical path from them.
    
	p := filepath.Join("dir1", "dir2", "filename")

    






    
    
	fmt.Println("p:", p)

    
p: dir1/dir2/filename







    
    
        
    

    






    
    
         You should always use `Join` instead of concatenating `/`s or `\`s manually. In addition to providing portability, `Join` will also normalize paths by removing superfluous separators and directory changes.
    
	fmt.Println(filepath.Join("dir1//", "filename"))

    
dir1/filename







    
    
	fmt.Println(filepath.Join("dir1/../dir1", "filename"))

    
dir1/filename







    
    
        
    

    






    
    
         `Dir` and `Base` can be used to split a path to the directory and the file. Alternatively, `Split` will return both in the same call.
    
	fmt.Println("Dir(p):", filepath.Dir(p))

    
Dir(p): dir1/dir2







    
    
	fmt.Println("Base(p):", filepath.Base(p))

    
Base(p): filename







    
    
        
    

    






    
    
         We can check whether a path is absolute.
    
	fmt.Println(filepath.IsAbs("dir/file"))

    
false







    
    
	fmt.Println(filepath.IsAbs("/dir/file"))

    
true







    
    
        
    

    






    
    
	filename := "config.json"

    






    
    
        
    

    






    
    
         Some file names have extensions following a dot. We can split the extension out of such names with `Ext`.
    
	ext := filepath.Ext(filename)

    






    
    
	fmt.Println(ext)

    
.json







    
    
        
    

    






    
    
         To find the file's name with the extension removed, use `strings.TrimSuffix`.
    
	fmt.Println(strings.TrimSuffix(filename, ext))

    
config







    
    
        
    

    






    
    
         `Rel` finds a relative path between a *base* and a *target*. It returns an error if the target cannot be made relative to base.
    
	rel, err := filepath.Rel("a/b", "a/b/t/file")

    






    
    
	if err != nil {

    






    
    
		panic(err)

    






    
    
	}

    






    
    
	fmt.Println(rel)

    
t/file







    
    
        
    

    






    
    
	rel, err = filepath.Rel("a/b", "a/c/t/file")

    






    
    
	if err != nil {

    






    
    
		panic(err)

    






    
    
	}

    






    
    
	fmt.Println(rel)

    
../c/t/file







    
    
}

    






    
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