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 5 package os 6 7 import ( 8 "errors" 9 ) 10 11 // Portable analogs of some common system call errors. 12 var ( 13 ErrInvalid = errors.New("invalid argument") 14 ErrPermission = errors.New("permission denied") 15 ErrExist = errors.New("file already exists") 16 ErrNotExist = errors.New("file does not exist") 17 ) 18 19 // PathError records an error and the operation and file path that caused it. 20 type PathError struct { 21 Op string 22 Path string 23 Err error 24 } 25 26 func (e *PathError) Error() string { return e.Op + " " + e.Path + ": " + e.Err.Error() } 27 28 // SyscallError records an error from a specific system call. 29 type SyscallError struct { 30 Syscall string 31 Err error 32 } 33 34 func (e *SyscallError) Error() string { return e.Syscall + ": " + e.Err.Error() } 35 36 // NewSyscallError returns, as an error, a new SyscallError 37 // with the given system call name and error details. 38 // As a convenience, if err is nil, NewSyscallError returns nil. 39 func NewSyscallError(syscall string, err error) error { 40 if err == nil { 41 return nil 42 } 43 return &SyscallError{syscall, err} 44 } 45 46 // IsExist returns a boolean indicating whether the error is known to report 47 // that a file or directory already exists. It is satisfied by ErrExist as 48 // well as some syscall errors. 49 func IsExist(err error) bool { 50 return isExist(err) 51 } 52 53 // IsNotExist returns a boolean indicating whether the error is known to 54 // report that a file or directory does not exist. It is satisfied by 55 // ErrNotExist as well as some syscall errors. 56 func IsNotExist(err error) bool { 57 return isNotExist(err) 58 } 59 60 // IsPermission returns a boolean indicating whether the error is known to 61 // report that permission is denied. It is satisfied by ErrPermission as well 62 // as some syscall errors. 63 func IsPermission(err error) bool { 64 return isPermission(err) 65 } 66
