1// Copyright 2009 The Go Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style
3// license that can be found in the LICENSE file.
4
5package os
6
7import (
8	"io/fs"
9	"syscall"
10)
11
12// Getpagesize returns the underlying system's memory page size.
13func Getpagesize() int { return syscall.Getpagesize() }
14
15// File represents an open file descriptor.
16type File struct {
17	*file // os specific
18}
19
20// A FileInfo describes a file and is returned by Stat and Lstat.
21type FileInfo = fs.FileInfo
22
23// A FileMode represents a file's mode and permission bits.
24// The bits have the same definition on all systems, so that
25// information about files can be moved from one system
26// to another portably. Not all bits apply to all systems.
27// The only required bit is ModeDir for directories.
28type FileMode = fs.FileMode
29
30// The defined file mode bits are the most significant bits of the FileMode.
31// The nine least-significant bits are the standard Unix rwxrwxrwx permissions.
32// The values of these bits should be considered part of the public API and
33// may be used in wire protocols or disk representations: they must not be
34// changed, although new bits might be added.
35const (
36	// The single letters are the abbreviations
37	// used by the String method's formatting.
38	ModeDir        = fs.ModeDir        // d: is a directory
39	ModeAppend     = fs.ModeAppend     // a: append-only
40	ModeExclusive  = fs.ModeExclusive  // l: exclusive use
41	ModeTemporary  = fs.ModeTemporary  // T: temporary file; Plan 9 only
42	ModeSymlink    = fs.ModeSymlink    // L: symbolic link
43	ModeDevice     = fs.ModeDevice     // D: device file
44	ModeNamedPipe  = fs.ModeNamedPipe  // p: named pipe (FIFO)
45	ModeSocket     = fs.ModeSocket     // S: Unix domain socket
46	ModeSetuid     = fs.ModeSetuid     // u: setuid
47	ModeSetgid     = fs.ModeSetgid     // g: setgid
48	ModeCharDevice = fs.ModeCharDevice // c: Unix character device, when ModeDevice is set
49	ModeSticky     = fs.ModeSticky     // t: sticky
50	ModeIrregular  = fs.ModeIrregular  // ?: non-regular file; nothing else is known about this file
51
52	// Mask for the type bits. For regular files, none will be set.
53	ModeType = fs.ModeType
54
55	ModePerm = fs.ModePerm // Unix permission bits, 0o777
56)
57
58func (fs *fileStat) Name() string { return fs.name }
59func (fs *fileStat) IsDir() bool  { return fs.Mode().IsDir() }
60
61// SameFile reports whether fi1 and fi2 describe the same file.
62// For example, on Unix this means that the device and inode fields
63// of the two underlying structures are identical; on other systems
64// the decision may be based on the path names.
65// SameFile only applies to results returned by this package's Stat.
66// It returns false in other cases.
67func SameFile(fi1, fi2 FileInfo) bool {
68	fs1, ok1 := fi1.(*fileStat)
69	fs2, ok2 := fi2.(*fileStat)
70	if !ok1 || !ok2 {
71		return false
72	}
73	return sameFile(fs1, fs2)
74}
75