1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
|
// Copyright 2011 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package exec
import (
"errors"
"os"
"strings"
)
// ErrNotFound is the error resulting if a path search failed to find an executable file.
var ErrNotFound = errors.New("executable file not found in $path")
func findExecutable(file string) error {
d, err := os.Stat(file)
if err != nil {
return err
}
if m := d.Mode(); !m.IsDir() && m&0111 != 0 {
return nil
}
return os.ErrPermission
}
// LookPath searches for an executable binary named file
// in the directories named by the path environment variable.
// If file begins with "/", "#", "./", or "../", it is tried
// directly and the path is not consulted.
func LookPath(file string) (string, error) {
// skip the path lookup for these prefixes
skip := []string{"/", "#", "./", "../"}
for _, p := range skip {
if strings.HasPrefix(file, p) {
err := findExecutable(file)
if err == nil {
return file, nil
}
return "", &Error{file, err}
}
}
path := os.Getenv("path")
for _, dir := range strings.Split(path, "\000") {
if err := findExecutable(dir + "/" + file); err == nil {
return dir + "/" + file, nil
}
}
return "", &Error{file, ErrNotFound}
}
|
