1 files changed, 22 insertions, 56 deletions
diff --git a/src/pkg/os/error_posix.go b/src/pkg/os/error_posix.go
index 1a0862725..74b75d112 100644
--- a/src/pkg/os/error_posix.go
+++ b/src/pkg/os/error_posix.go
@@ -6,65 +6,31 @@
 
 package os
 
-import syscall "syscall"
+import "syscall"
 
-// Commonly known Unix errors.
-var (
-	EPERM        error = syscall.EPERM
-	ENOENT       error = syscall.ENOENT
-	ESRCH        error = syscall.ESRCH
-	EINTR        error = syscall.EINTR
-	EIO          error = syscall.EIO
-	ENXIO        error = syscall.ENXIO
-	E2BIG        error = syscall.E2BIG
-	ENOEXEC      error = syscall.ENOEXEC
-	EBADF        error = syscall.EBADF
-	ECHILD       error = syscall.ECHILD
-	EDEADLK      error = syscall.EDEADLK
-	ENOMEM       error = syscall.ENOMEM
-	EACCES       error = syscall.EACCES
-	EFAULT       error = syscall.EFAULT
-	EBUSY        error = syscall.EBUSY
-	EEXIST       error = syscall.EEXIST
-	EXDEV        error = syscall.EXDEV
-	ENODEV       error = syscall.ENODEV
-	ENOTDIR      error = syscall.ENOTDIR
-	EISDIR       error = syscall.EISDIR
-	EINVAL       error = syscall.EINVAL
-	ENFILE       error = syscall.ENFILE
-	EMFILE       error = syscall.EMFILE
-	ENOTTY       error = syscall.ENOTTY
-	EFBIG        error = syscall.EFBIG
-	ENOSPC       error = syscall.ENOSPC
-	ESPIPE       error = syscall.ESPIPE
-	EROFS        error = syscall.EROFS
-	EMLINK       error = syscall.EMLINK
-	EPIPE        error = syscall.EPIPE
-	EAGAIN       error = syscall.EAGAIN
-	EDOM         error = syscall.EDOM
-	ERANGE       error = syscall.ERANGE
-	EADDRINUSE   error = syscall.EADDRINUSE
-	ECONNREFUSED error = syscall.ECONNREFUSED
-	ENAMETOOLONG error = syscall.ENAMETOOLONG
-	EAFNOSUPPORT error = syscall.EAFNOSUPPORT
-	ETIMEDOUT    error = syscall.ETIMEDOUT
-	ENOTCONN     error = syscall.ENOTCONN
-)
-
-// SyscallError records an error from a specific system call.
-type SyscallError struct {
-	Syscall string
-	Errno   error
+// IsExist returns whether the error is known to report that a file already exists.
+// It is satisfied by ErrExist as well as some syscall errors.
+func IsExist(err error) bool {
+	if pe, ok := err.(*PathError); ok {
+		err = pe.Err
+	}
+	return err == syscall.EEXIST || err == ErrExist
 }
 
-func (e *SyscallError) Error() string { return e.Syscall + ": " + e.Errno.Error() }
+// IsNotExist returns whether the error is known to report that a file does not exist.
+// It is satisfied by ErrNotExist as well as some syscall errors.
+func IsNotExist(err error) bool {
+	if pe, ok := err.(*PathError); ok {
+		err = pe.Err
+	}
+	return err == syscall.ENOENT || err == ErrNotExist
+}
 
-// NewSyscallError returns, as an error, a new SyscallError
-// with the given system call name and error details.
-// As a convenience, if err is nil, NewSyscallError returns nil.
-func NewSyscallError(syscall string, err error) error {
-	if err == nil {
-		return nil
+// IsPermission returns whether the error is known to report that permission is denied.
+// It is satisfied by ErrPermission as well as some syscall errors.
+func IsPermission(err error) bool {
+	if pe, ok := err.(*PathError); ok {
+		err = pe.Err
 	}
-	return &SyscallError{syscall, err}
+	return err == syscall.EACCES || err == syscall.EPERM || err == ErrPermission
 }