| // Copyright 2009 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 file |
| |
| import ( |
| "os" |
| "syscall" |
| ) |
| |
| type File struct { |
| fd int // file descriptor number |
| name string // file name at Open time |
| } |
| |
| func newFile(fd int, name string) *File { |
| if fd < 0 { |
| return nil |
| } |
| return &File{fd, name} |
| } |
| |
| var ( |
| Stdin = newFile(0, "/dev/stdin") |
| Stdout = newFile(1, "/dev/stdout") |
| Stderr = newFile(2, "/dev/stderr") |
| ) |
| |
| func Open(name string, mode int, perm uint32) (file *File, err os.Error) { |
| r, e := syscall.Open(name, mode, perm) |
| if e != 0 { |
| err = os.Errno(e) |
| } |
| return newFile(r, name), err |
| } |
| |
| func (file *File) Close() os.Error { |
| if file == nil { |
| return os.EINVAL |
| } |
| e := syscall.Close(file.fd) |
| file.fd = -1 // so it can't be closed again |
| if e != 0 { |
| return os.Errno(e) |
| } |
| return nil |
| } |
| |
| func (file *File) Read(b []byte) (ret int, err os.Error) { |
| if file == nil { |
| return -1, os.EINVAL |
| } |
| r, e := syscall.Read(file.fd, b) |
| if e != 0 { |
| err = os.Errno(e) |
| } |
| return int(r), err |
| } |
| |
| func (file *File) Write(b []byte) (ret int, err os.Error) { |
| if file == nil { |
| return -1, os.EINVAL |
| } |
| r, e := syscall.Write(file.fd, b) |
| if e != 0 { |
| err = os.Errno(e) |
| } |
| return int(r), err |
| } |
| |
| func (file *File) String() string { |
| return file.name |
| } |