diff --git a/CHANGELOG.md b/CHANGELOG.md
index dce9e49..4162b26 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+#### 2.2.0
+
+* Added `ErrorCodes` class, which holds errno values.
+
 #### 2.1.0
 
 * Add support for new `dart:io` API methods added in Dart SDK 1.23
diff --git a/lib/src/backends/chroot/chroot_directory.dart b/lib/src/backends/chroot/chroot_directory.dart
index 23d24c3..102a1c1 100644
--- a/lib/src/backends/chroot/chroot_directory.dart
+++ b/lib/src/backends/chroot/chroot_directory.dart
@@ -30,18 +30,18 @@ class _ChrootDirectory extends _ChrootFileSystemEntity<Directory, io.Directory>
   Future<Directory> rename(String newPath) async {
     if (_isLink) {
       if (await fileSystem.type(path) != expectedType) {
-        throw new FileSystemException('Not a directory', path);
+        throw common.notADirectory(path);
       }
       FileSystemEntityType type = await fileSystem.type(newPath);
       if (type != FileSystemEntityType.NOT_FOUND) {
         if (type != expectedType) {
-          throw new FileSystemException('Not a directory', newPath);
+          throw common.notADirectory(newPath);
         }
         if (!(await fileSystem
             .directory(newPath)
             .list(followLinks: false)
             .isEmpty)) {
-          throw new FileSystemException('Directory not empty', newPath);
+          throw common.directoryNotEmpty(newPath);
         }
       }
       String target = await fileSystem.link(path).target();
@@ -58,18 +58,18 @@ class _ChrootDirectory extends _ChrootFileSystemEntity<Directory, io.Directory>
   Directory renameSync(String newPath) {
     if (_isLink) {
       if (fileSystem.typeSync(path) != expectedType) {
-        throw new FileSystemException('Not a directory', path);
+        throw common.notADirectory(path);
       }
       FileSystemEntityType type = fileSystem.typeSync(newPath);
       if (type != FileSystemEntityType.NOT_FOUND) {
         if (type != expectedType) {
-          throw new FileSystemException('Not a directory', newPath);
+          throw common.notADirectory(newPath);
         }
         if (fileSystem
             .directory(newPath)
             .listSync(followLinks: false)
             .isNotEmpty) {
-          throw new FileSystemException('Directory not empty', newPath);
+          throw common.directoryNotEmpty(newPath);
         }
       }
       String target = fileSystem.link(path).targetSync();
@@ -99,9 +99,9 @@ class _ChrootDirectory extends _ChrootFileSystemEntity<Directory, io.Directory>
     if (_isLink) {
       switch (await fileSystem.type(path)) {
         case FileSystemEntityType.NOT_FOUND:
-          throw new FileSystemException('No such file or directory', path);
+          throw common.noSuchFileOrDirectory(path);
         case FileSystemEntityType.FILE:
-          throw new FileSystemException('File exists', path);
+          throw common.fileExists(path);
         case FileSystemEntityType.DIRECTORY:
           // Nothing to do.
           return this;
@@ -118,9 +118,9 @@ class _ChrootDirectory extends _ChrootFileSystemEntity<Directory, io.Directory>
     if (_isLink) {
       switch (fileSystem.typeSync(path)) {
         case FileSystemEntityType.NOT_FOUND:
-          throw new FileSystemException('No such file or directory', path);
+          throw common.noSuchFileOrDirectory(path);
         case FileSystemEntityType.FILE:
-          throw new FileSystemException('File exists', path);
+          throw common.fileExists(path);
         case FileSystemEntityType.DIRECTORY:
           // Nothing to do.
           return;
diff --git a/lib/src/backends/chroot/chroot_file.dart b/lib/src/backends/chroot/chroot_file.dart
index 74d8cc9..3e12c43 100644
--- a/lib/src/backends/chroot/chroot_file.dart
+++ b/lib/src/backends/chroot/chroot_file.dart
@@ -45,7 +45,7 @@ class _ChrootFile extends _ChrootFileSystemEntity<File, io.File>
           };
           break;
         case FileSystemEntityType.DIRECTORY:
-          throw new FileSystemException('Is a directory', newPath);
+          throw common.isADirectory(newPath);
         default:
           // Should never happen.
           throw new AssertionError();
@@ -55,9 +55,9 @@ class _ChrootFile extends _ChrootFileSystemEntity<File, io.File>
     if (_isLink) {
       switch (await fileSystem.type(path)) {
         case FileSystemEntityType.NOT_FOUND:
-          throw new FileSystemException('No such file or directory', path);
+          throw common.noSuchFileOrDirectory(path);
         case FileSystemEntityType.DIRECTORY:
-          throw new FileSystemException('Is a directory', path);
+          throw common.isADirectory(path);
         case FileSystemEntityType.FILE:
           await setUp();
           await fileSystem.delegate
@@ -94,7 +94,7 @@ class _ChrootFile extends _ChrootFileSystemEntity<File, io.File>
           };
           break;
         case FileSystemEntityType.DIRECTORY:
-          throw new FileSystemException('Is a directory', newPath);
+          throw common.isADirectory(newPath);
         default:
           // Should never happen.
           throw new AssertionError();
@@ -104,9 +104,9 @@ class _ChrootFile extends _ChrootFileSystemEntity<File, io.File>
     if (_isLink) {
       switch (fileSystem.typeSync(path)) {
         case FileSystemEntityType.NOT_FOUND:
-          throw new FileSystemException('No such file or directory', path);
+          throw common.noSuchFileOrDirectory(path);
         case FileSystemEntityType.DIRECTORY:
-          throw new FileSystemException('Is a directory', path);
+          throw common.isADirectory(path);
         case FileSystemEntityType.FILE:
           setUp();
           fileSystem.delegate
@@ -149,7 +149,7 @@ class _ChrootFile extends _ChrootFileSystemEntity<File, io.File>
           // Nothing to do.
           return this;
         case FileSystemEntityType.DIRECTORY:
-          throw new FileSystemException('Is a directory', path);
+          throw common.isADirectory(path);
         default:
           throw new AssertionError();
       }
@@ -181,7 +181,7 @@ class _ChrootFile extends _ChrootFileSystemEntity<File, io.File>
           // Nothing to do.
           return;
         case FileSystemEntityType.DIRECTORY:
-          throw new FileSystemException('Is a directory', path);
+          throw common.isADirectory(path);
         default:
           throw new AssertionError();
       }
diff --git a/lib/src/backends/chroot/chroot_file_system.dart b/lib/src/backends/chroot/chroot_file_system.dart
index d3c861b..ae5135d 100644
--- a/lib/src/backends/chroot/chroot_file_system.dart
+++ b/lib/src/backends/chroot/chroot_file_system.dart
@@ -114,9 +114,9 @@ class ChrootFileSystem extends FileSystem {
       case FileSystemEntityType.DIRECTORY:
         break;
       case FileSystemEntityType.NOT_FOUND:
-        throw new FileSystemException('No such file or directory');
+        throw common.noSuchFileOrDirectory(path);
       default:
-        throw new FileSystemException('Not a directory');
+        throw common.notADirectory(path);
     }
     assert(() {
       p.Context ctx = delegate.path;
@@ -299,7 +299,7 @@ class ChrootFileSystem extends FileSystem {
         case FileSystemEntityType.FILE:
           breadcrumbs.clear();
           if (parts.isNotEmpty) {
-            throw new FileSystemException('Not a directory', currentPath);
+            throw common.notADirectory(currentPath);
           }
           break;
         case FileSystemEntityType.NOT_FOUND:
@@ -308,10 +308,6 @@ class ChrootFileSystem extends FileSystem {
             return getCurrentPath();
           }
 
-          FileSystemException notFoundException() {
-            return new FileSystemException('No such file or directory', path);
-          }
-
           switch (notFound) {
             case _NotFoundBehavior.mkdir:
               if (parts.isNotEmpty) {
@@ -324,9 +320,9 @@ class ChrootFileSystem extends FileSystem {
               if (parts.isEmpty) {
                 return returnEarly();
               }
-              throw notFoundException();
+              throw common.noSuchFileOrDirectory(path);
             case _NotFoundBehavior.throwError:
-              throw notFoundException();
+              throw common.noSuchFileOrDirectory(path);
           }
           break;
         case FileSystemEntityType.LINK:
@@ -334,8 +330,7 @@ class ChrootFileSystem extends FileSystem {
             break;
           }
           if (!breadcrumbs.add(currentPath)) {
-            throw new FileSystemException(
-                'Too many levels of symbolic links', path);
+            throw common.tooManyLevelsOfSymbolicLinks(path);
           }
           String target = delegate.link(realPath).targetSync();
           if (ctx.isAbsolute(target)) {
diff --git a/lib/src/backends/chroot/chroot_file_system_entity.dart b/lib/src/backends/chroot/chroot_file_system_entity.dart
index 89b1487..ed777de 100644
--- a/lib/src/backends/chroot/chroot_file_system_entity.dart
+++ b/lib/src/backends/chroot/chroot_file_system_entity.dart
@@ -116,10 +116,9 @@ abstract class _ChrootFileSystemEntity<T extends FileSystemEntity,
         String resolvedPath = fileSystem._resolve(p.basename(path),
             from: p.dirname(path), notFound: _NotFoundBehavior.allowAtTail);
         if (!recursive && await type(resolvedPath) != expectedType) {
-          String msg = expectedType == FileSystemEntityType.FILE
-              ? 'Is a directory'
-              : 'Not a directory';
-          throw new FileSystemException(msg, path);
+          throw expectedType == FileSystemEntityType.FILE
+              ? common.isADirectory(path)
+              : common.notADirectory(path);
         }
         await fileSystem.delegate.link(real(path)).delete();
       }
@@ -146,10 +145,9 @@ abstract class _ChrootFileSystemEntity<T extends FileSystemEntity,
         String resolvedPath = fileSystem._resolve(p.basename(path),
             from: p.dirname(path), notFound: _NotFoundBehavior.allowAtTail);
         if (!recursive && type(resolvedPath) != expectedType) {
-          String msg = expectedType == FileSystemEntityType.FILE
-              ? 'Is a directory'
-              : 'Not a directory';
-          throw new FileSystemException(msg, path);
+          throw expectedType == FileSystemEntityType.FILE
+              ? common.isADirectory(path)
+              : common.notADirectory(path);
         }
         fileSystem.delegate.link(real(path)).deleteSync();
       }
diff --git a/lib/src/backends/memory/memory_directory.dart b/lib/src/backends/memory/memory_directory.dart
index 34793df..3a3cbb1 100644
--- a/lib/src/backends/memory/memory_directory.dart
+++ b/lib/src/backends/memory/memory_directory.dart
@@ -39,7 +39,7 @@ class _MemoryDirectory extends _MemoryFileSystemEntity implements Directory {
     );
     if (node.type != expectedType) {
       // There was an existing non-directory node at this object's path
-      throw new io.FileSystemException('File exists', path);
+      throw common.notADirectory(path);
     }
   }
 
@@ -73,7 +73,7 @@ class _MemoryDirectory extends _MemoryFileSystemEntity implements Directory {
         newPath,
         validateOverwriteExistingEntity: (_DirectoryNode existingNode) {
           if (existingNode.children.isNotEmpty) {
-            throw new io.FileSystemException('Directory not empty', newPath);
+            throw common.directoryNotEmpty(newPath);
           }
         },
       );
diff --git a/lib/src/backends/memory/memory_file.dart b/lib/src/backends/memory/memory_file.dart
index ded6bfa..6d9368e 100644
--- a/lib/src/backends/memory/memory_file.dart
+++ b/lib/src/backends/memory/memory_file.dart
@@ -51,7 +51,7 @@ class _MemoryFile extends _MemoryFileSystemEntity implements File {
     if (node.type != expectedType) {
       // There was an existing non-file entity at this object's path
       assert(node.type == FileSystemEntityType.DIRECTORY);
-      throw new io.FileSystemException('Is a directory', path);
+      throw common.isADirectory(path);
     }
     return node;
   }
@@ -66,10 +66,9 @@ class _MemoryFile extends _MemoryFileSystemEntity implements File {
         checkType: (_Node node) {
           FileSystemEntityType actualType = node.stat.type;
           if (actualType != expectedType) {
-            String msg = actualType == FileSystemEntityType.NOT_FOUND
-                ? 'No such file or directory'
-                : 'Is a directory';
-            throw new FileSystemException(msg, path);
+            throw actualType == FileSystemEntityType.NOT_FOUND
+                ? common.noSuchFileOrDirectory(path)
+                : common.isADirectory(path);
           }
         },
       );
@@ -231,7 +230,7 @@ class _MemoryFile extends _MemoryFileSystemEntity implements File {
     bool flush: false,
   }) {
     if (!_isWriteMode(mode)) {
-      throw new FileSystemException('Bad file descriptor', path);
+      throw common.badFileDescriptor(path);
     }
     _FileNode node = _resolvedBackingOrCreate;
     _truncateIfNecessary(node, mode);
diff --git a/lib/src/backends/memory/memory_file_system_entity.dart b/lib/src/backends/memory/memory_file_system_entity.dart
index b5fdcee..dfe23f9 100644
--- a/lib/src/backends/memory/memory_file_system_entity.dart
+++ b/lib/src/backends/memory/memory_file_system_entity.dart
@@ -261,7 +261,7 @@ abstract class _MemoryFileSystemEntity implements FileSystemEntity {
     _Node node = _backing;
     if (!recursive) {
       if (node is _DirectoryNode && node.children.isNotEmpty) {
-        throw new io.FileSystemException('Directory not empty', path);
+        throw common.directoryNotEmpty(path);
       }
       (checkType ?? _defaultCheckType)(node);
     }
diff --git a/lib/src/backends/memory/memory_link.dart b/lib/src/backends/memory/memory_link.dart
index 2d63646..e141584 100644
--- a/lib/src/backends/memory/memory_link.dart
+++ b/lib/src/backends/memory/memory_link.dart
@@ -22,10 +22,9 @@ class _MemoryLink extends _MemoryFileSystemEntity implements Link {
         newPath,
         checkType: (_Node node) {
           if (node.type != expectedType) {
-            throw new FileSystemException(
-                node.type == FileSystemEntityType.DIRECTORY
-                    ? 'Is a directory'
-                    : 'Invalid argument');
+            throw node.type == FileSystemEntityType.DIRECTORY
+                ? common.isADirectory(newPath)
+                : common.invalidArgument(newPath);
           }
         },
       );
@@ -50,7 +49,7 @@ class _MemoryLink extends _MemoryFileSystemEntity implements Link {
     });
     if (preexisting) {
       // Per the spec, this is an error.
-      throw new io.FileSystemException('File exists', path);
+      throw common.fileExists(path);
     }
   }
 
@@ -82,7 +81,7 @@ class _MemoryLink extends _MemoryFileSystemEntity implements Link {
     _Node node = _backing;
     if (node.type != expectedType) {
       // Note: this may change; https://github.com/dart-lang/sdk/issues/28204
-      throw new FileSystemException('No such file or directory', path);
+      throw common.noSuchFileOrDirectory(path);
     }
     return (node as _LinkNode).target;
   }
diff --git a/lib/src/backends/memory/utils.dart b/lib/src/backends/memory/utils.dart
index b62e079..72059af 100644
--- a/lib/src/backends/memory/utils.dart
+++ b/lib/src/backends/memory/utils.dart
@@ -27,14 +27,14 @@ typedef void _TypeChecker(_Node node);
 /// Throws a [io.FileSystemException] if [node] is null.
 void _checkExists(_Node node, _PathGenerator path) {
   if (node == null) {
-    throw new io.FileSystemException('No such file or directory', path());
+    throw common.noSuchFileOrDirectory(path());
   }
 }
 
 /// Throws a [io.FileSystemException] if [node] is not a directory.
 void _checkIsDir(_Node node, _PathGenerator path) {
   if (!_isDirectory(node)) {
-    throw new io.FileSystemException('Not a directory', path());
+    throw common.notADirectory(path());
   }
 }
 
@@ -46,23 +46,18 @@ void _checkType(
   _PathGenerator path,
 ) {
   if (expectedType != actualType) {
-    String msg;
     switch (expectedType) {
       case FileSystemEntityType.DIRECTORY:
-        msg = 'Not a directory';
-        break;
+        throw common.notADirectory(path());
       case FileSystemEntityType.FILE:
         assert(actualType == FileSystemEntityType.DIRECTORY);
-        msg = 'Is a directory';
-        break;
+        throw common.isADirectory(path());
       case FileSystemEntityType.LINK:
-        msg = 'Invalid argument';
-        break;
+        throw common.invalidArgument(path());
       default:
         // Should not happen
         throw new AssertionError();
     }
-    throw new io.FileSystemException(msg, path());
   }
 }
 
@@ -111,8 +106,7 @@ _Node _resolveLinks(
   while (_isLink(node)) {
     link = node;
     if (!breadcrumbs.add(node)) {
-      throw new io.FileSystemException(
-          'Too many levels of symbolic links', path());
+      throw common.tooManyLevelsOfSymbolicLinks(path());
     }
     if (ledger != null) {
       if (_isAbsolute(link.target)) {
diff --git a/lib/src/common.dart b/lib/src/common.dart
index 24dc7be..87148c5 100644
--- a/lib/src/common.dart
+++ b/lib/src/common.dart
@@ -2,7 +2,8 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-import 'package:file/src/io.dart' as io;
+import 'interface.dart';
+import 'io.dart' as io;
 
 /// Gets the string path represented by the specified generic [path].
 String getPath(dynamic path) {
@@ -16,3 +17,49 @@ String getPath(dynamic path) {
     throw new ArgumentError('Invalid type for "path": ${path?.runtimeType}');
   }
 }
+
+/// Returns a 'No such file or directory' [FileSystemException].
+FileSystemException noSuchFileOrDirectory(String path) {
+  return _fsException(path, 'No such file or directory', ErrorCodes.ENOENT);
+}
+
+/// Returns a 'Not a directory' [FileSystemException].
+FileSystemException notADirectory(String path) {
+  return _fsException(path, 'Not a directory', ErrorCodes.ENOTDIR);
+}
+
+/// Returns a 'Is a directory' [FileSystemException].
+FileSystemException isADirectory(String path) {
+  return _fsException(path, 'Is a directory', ErrorCodes.EISDIR);
+}
+
+/// Returns a 'Directory not empty' [FileSystemException].
+FileSystemException directoryNotEmpty(String path) {
+  return _fsException(path, 'Directory not empty', ErrorCodes.ENOTEMPTY);
+}
+
+/// Returns a 'File exists' [FileSystemException].
+FileSystemException fileExists(String path) {
+  return _fsException(path, 'File exists', ErrorCodes.EEXIST);
+}
+
+/// Returns a 'Invalid argument' [FileSystemException].
+FileSystemException invalidArgument(String path) {
+  return _fsException(path, 'Invalid argument', ErrorCodes.EINVAL);
+}
+
+/// Returns a 'Too many levels of symbolic links' [FileSystemException].
+FileSystemException tooManyLevelsOfSymbolicLinks(String path) {
+  // TODO(tvolkert): Switch to ErrorCodes.EMLINK
+  return _fsException(
+      path, 'Too many levels of symbolic links', ErrorCodes.ELOOP);
+}
+
+/// Returns a 'Bad file descriptor' [FileSystemException].
+FileSystemException badFileDescriptor(String path) {
+  return _fsException(path, 'Bad file descriptor', ErrorCodes.EBADF);
+}
+
+FileSystemException _fsException(String path, String msg, int errorCode) {
+  return new FileSystemException(msg, path, new OSError(msg, errorCode));
+}
diff --git a/lib/src/interface.dart b/lib/src/interface.dart
index db86876..4662e35 100644
--- a/lib/src/interface.dart
+++ b/lib/src/interface.dart
@@ -4,17 +4,10 @@
 
 library file.src.interface;
 
-import 'dart:async';
-import 'dart:convert';
-
-import 'package:path/path.dart' as path;
-
-import 'io.dart' as io;
-
-export 'io.dart';
-
-part 'interface/directory.dart';
-part 'interface/file.dart';
-part 'interface/file_system.dart';
-part 'interface/file_system_entity.dart';
-part 'interface/link.dart';
+export 'interface/directory.dart';
+export 'interface/error_codes.dart';
+export 'interface/file.dart';
+export 'interface/file_system.dart';
+export 'interface/file_system_entity.dart';
+export 'interface/link.dart';
+export 'io.dart' hide Directory, File, FileSystemEntity, Link;
diff --git a/lib/src/interface/directory.dart b/lib/src/interface/directory.dart
index 10740ca..f19c67f 100644
--- a/lib/src/interface/directory.dart
+++ b/lib/src/interface/directory.dart
@@ -2,7 +2,10 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-part of file.src.interface;
+import 'dart:async';
+
+import 'file_system_entity.dart';
+import '../io.dart' as io;
 
 /// A reference to a directory on the file system.
 abstract class Directory implements FileSystemEntity, io.Directory {
diff --git a/lib/src/interface/error_codes.dart b/lib/src/interface/error_codes.dart
new file mode 100644
index 0000000..48fc5db
--- /dev/null
+++ b/lib/src/interface/error_codes.dart
@@ -0,0 +1,585 @@
+// Copyright (c) 2017, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'error_codes_internal.dart'
+    if (dart.library.io) 'error_codes_dart_io.dart';
+
+/// Operating system error codes.
+// TODO(tvolkert): Remove (https://github.com/dart-lang/sdk/issues/28860)
+class ErrorCodes {
+  ErrorCodes._();
+
+  /// Argument list too long
+  // ignore: non_constant_identifier_names
+  static int get E2BIG => _platform((_Codes codes) => codes.e2big);
+
+  /// Permission denied
+  // ignore: non_constant_identifier_names
+  static int get EACCES => _platform((_Codes codes) => codes.eacces);
+
+  /// Try again
+  // ignore: non_constant_identifier_names
+  static int get EAGAIN => _platform((_Codes codes) => codes.eagain);
+
+  /// Bad file number
+  // ignore: non_constant_identifier_names
+  static int get EBADF => _platform((_Codes codes) => codes.ebadf);
+
+  /// Device or resource busy
+  // ignore: non_constant_identifier_names
+  static int get EBUSY => _platform((_Codes codes) => codes.ebusy);
+
+  /// No child processes
+  // ignore: non_constant_identifier_names
+  static int get ECHILD => _platform((_Codes codes) => codes.echild);
+
+  /// Resource deadlock would occur
+  // ignore: non_constant_identifier_names
+  static int get EDEADLK => _platform((_Codes codes) => codes.edeadlk);
+
+  /// Math argument out of domain of func
+  // ignore: non_constant_identifier_names
+  static int get EDOM => _platform((_Codes codes) => codes.edom);
+
+  /// File exists
+  // ignore: non_constant_identifier_names
+  static int get EEXIST => _platform((_Codes codes) => codes.eexist);
+
+  /// Bad address
+  // ignore: non_constant_identifier_names
+  static int get EFAULT => _platform((_Codes codes) => codes.efault);
+
+  /// File too large
+  // ignore: non_constant_identifier_names
+  static int get EFBIG => _platform((_Codes codes) => codes.efbig);
+
+  /// Illegal byte sequence
+  // ignore: non_constant_identifier_names
+  static int get EILSEQ => _platform((_Codes codes) => codes.eilseq);
+
+  /// Interrupted system call
+  // ignore: non_constant_identifier_names
+  static int get EINTR => _platform((_Codes codes) => codes.eintr);
+
+  /// Invalid argument
+  // ignore: non_constant_identifier_names
+  static int get EINVAL => _platform((_Codes codes) => codes.einval);
+
+  /// I/O error
+  // ignore: non_constant_identifier_names
+  static int get EIO => _platform((_Codes codes) => codes.eio);
+
+  /// Is a directory
+  // ignore: non_constant_identifier_names
+  static int get EISDIR => _platform((_Codes codes) => codes.eisdir);
+
+  /// Too many levels of symbolic links
+  // ignore: non_constant_identifier_names
+  static int get ELOOP => _platform((_Codes codes) => codes.eloop);
+
+  /// Too many open files
+  // ignore: non_constant_identifier_names
+  static int get EMFILE => _platform((_Codes codes) => codes.emfile);
+
+  /// Too many links
+  // ignore: non_constant_identifier_names
+  static int get EMLINK => _platform((_Codes codes) => codes.emlink);
+
+  /// File name too long
+  // ignore: non_constant_identifier_names
+  static int get ENAMETOOLONG =>
+      _platform((_Codes codes) => codes.enametoolong);
+
+  /// File table overflow
+  // ignore: non_constant_identifier_names
+  static int get ENFILE => _platform((_Codes codes) => codes.enfile);
+
+  /// No such device
+  // ignore: non_constant_identifier_names
+  static int get ENODEV => _platform((_Codes codes) => codes.enodev);
+
+  /// No such file or directory
+  // ignore: non_constant_identifier_names
+  static int get ENOENT => _platform((_Codes codes) => codes.enoent);
+
+  /// Exec format error
+  // ignore: non_constant_identifier_names
+  static int get ENOEXEC => _platform((_Codes codes) => codes.enoexec);
+
+  /// No record locks available
+  // ignore: non_constant_identifier_names
+  static int get ENOLCK => _platform((_Codes codes) => codes.enolck);
+
+  /// Out of memory
+  // ignore: non_constant_identifier_names
+  static int get ENOMEM => _platform((_Codes codes) => codes.enomem);
+
+  /// No space left on device
+  // ignore: non_constant_identifier_names
+  static int get ENOSPC => _platform((_Codes codes) => codes.enospc);
+
+  /// Function not implemented
+  // ignore: non_constant_identifier_names
+  static int get ENOSYS => _platform((_Codes codes) => codes.enosys);
+
+  /// Not a directory
+  // ignore: non_constant_identifier_names
+  static int get ENOTDIR => _platform((_Codes codes) => codes.enotdir);
+
+  /// Directory not empty
+  // ignore: non_constant_identifier_names
+  static int get ENOTEMPTY => _platform((_Codes codes) => codes.enotempty);
+
+  /// Not a typewriter
+  // ignore: non_constant_identifier_names
+  static int get ENOTTY => _platform((_Codes codes) => codes.enotty);
+
+  /// No such device or address
+  // ignore: non_constant_identifier_names
+  static int get ENXIO => _platform((_Codes codes) => codes.enxio);
+
+  /// Operation not permitted
+  // ignore: non_constant_identifier_names
+  static int get EPERM => _platform((_Codes codes) => codes.eperm);
+
+  /// Broken pipe
+  // ignore: non_constant_identifier_names
+  static int get EPIPE => _platform((_Codes codes) => codes.epipe);
+
+  /// Math result not representable
+  // ignore: non_constant_identifier_names
+  static int get ERANGE => _platform((_Codes codes) => codes.erange);
+
+  /// Read-only file system
+  // ignore: non_constant_identifier_names
+  static int get EROFS => _platform((_Codes codes) => codes.erofs);
+
+  /// Illegal seek
+  // ignore: non_constant_identifier_names
+  static int get ESPIPE => _platform((_Codes codes) => codes.espipe);
+
+  /// No such process
+  // ignore: non_constant_identifier_names
+  static int get ESRCH => _platform((_Codes codes) => codes.esrch);
+
+  /// Cross-device link
+  // ignore: non_constant_identifier_names
+  static int get EXDEV => _platform((_Codes codes) => codes.exdev);
+
+  static int _platform(int getCode(_Codes codes)) {
+    _Codes codes = _platforms[operatingSystem];
+    return getCode(codes);
+  }
+}
+
+const Map<String, _Codes> _platforms = const <String, _Codes>{
+  'linux': const _LinuxCodes(),
+  'macos': const _MacOSCodes(),
+  'windows': const _WindowsCodes(),
+};
+
+abstract class _Codes {
+  int get e2big;
+  int get eacces;
+  int get eagain;
+  int get ebadf;
+  int get ebusy;
+  int get echild;
+  int get edeadlk;
+  int get edom;
+  int get eexist;
+  int get efault;
+  int get efbig;
+  int get eilseq;
+  int get eintr;
+  int get einval;
+  int get eio;
+  int get eisdir;
+  int get eloop;
+  int get emfile;
+  int get emlink;
+  int get enametoolong;
+  int get enfile;
+  int get enodev;
+  int get enoent;
+  int get enoexec;
+  int get enolck;
+  int get enomem;
+  int get enospc;
+  int get enosys;
+  int get enotdir;
+  int get enotempty;
+  int get enotty;
+  int get enxio;
+  int get eperm;
+  int get epipe;
+  int get erange;
+  int get erofs;
+  int get espipe;
+  int get esrch;
+  int get exdev;
+}
+
+class _LinuxCodes implements _Codes {
+  const _LinuxCodes();
+
+  @override
+  final int e2big = 7;
+
+  @override
+  final int eacces = 13;
+
+  @override
+  final int eagain = 11;
+
+  @override
+  final int ebadf = 9;
+
+  @override
+  final int ebusy = 16;
+
+  @override
+  final int echild = 10;
+
+  @override
+  final int edeadlk = 35;
+
+  @override
+  final int edom = 33;
+
+  @override
+  final int eexist = 17;
+
+  @override
+  final int efault = 14;
+
+  @override
+  final int efbig = 27;
+
+  @override
+  final int eilseq = 84;
+
+  @override
+  final int eintr = 4;
+
+  @override
+  final int einval = 22;
+
+  @override
+  final int eio = 5;
+
+  @override
+  final int eisdir = 21;
+
+  @override
+  final int eloop = 40;
+
+  @override
+  final int emfile = 24;
+
+  @override
+  final int emlink = 31;
+
+  @override
+  final int enametoolong = 36;
+
+  @override
+  final int enfile = 23;
+
+  @override
+  final int enodev = 19;
+
+  @override
+  final int enoent = 2;
+
+  @override
+  final int enoexec = 8;
+
+  @override
+  final int enolck = 37;
+
+  @override
+  final int enomem = 12;
+
+  @override
+  final int enospc = 28;
+
+  @override
+  final int enosys = 38;
+
+  @override
+  final int enotdir = 20;
+
+  @override
+  final int enotempty = 39;
+
+  @override
+  final int enotty = 25;
+
+  @override
+  final int enxio = 6;
+
+  @override
+  final int eperm = 1;
+
+  @override
+  final int epipe = 32;
+
+  @override
+  final int erange = 34;
+
+  @override
+  final int erofs = 30;
+
+  @override
+  final int espipe = 29;
+
+  @override
+  final int esrch = 3;
+
+  @override
+  final int exdev = 18;
+}
+
+class _MacOSCodes implements _Codes {
+  const _MacOSCodes();
+
+  @override
+  final int e2big = 7;
+
+  @override
+  final int eacces = 13;
+
+  @override
+  final int eagain = 35;
+
+  @override
+  final int ebadf = 9;
+
+  @override
+  final int ebusy = 16;
+
+  @override
+  final int echild = 10;
+
+  @override
+  final int edeadlk = 11;
+
+  @override
+  final int edom = 33;
+
+  @override
+  final int eexist = 17;
+
+  @override
+  final int efault = 14;
+
+  @override
+  final int efbig = 27;
+
+  @override
+  final int eilseq = 92;
+
+  @override
+  final int eintr = 4;
+
+  @override
+  final int einval = 22;
+
+  @override
+  final int eio = 5;
+
+  @override
+  final int eisdir = 21;
+
+  @override
+  final int eloop = 62;
+
+  @override
+  final int emfile = 24;
+
+  @override
+  final int emlink = 31;
+
+  @override
+  final int enametoolong = 63;
+
+  @override
+  final int enfile = 23;
+
+  @override
+  final int enodev = 19;
+
+  @override
+  final int enoent = 2;
+
+  @override
+  final int enoexec = 8;
+
+  @override
+  final int enolck = 77;
+
+  @override
+  final int enomem = 12;
+
+  @override
+  final int enospc = 28;
+
+  @override
+  final int enosys = 78;
+
+  @override
+  final int enotdir = 20;
+
+  @override
+  final int enotempty = 66;
+
+  @override
+  final int enotty = 25;
+
+  @override
+  final int enxio = 6;
+
+  @override
+  final int eperm = 1;
+
+  @override
+  final int epipe = 32;
+
+  @override
+  final int erange = 34;
+
+  @override
+  final int erofs = 30;
+
+  @override
+  final int espipe = 29;
+
+  @override
+  final int esrch = 3;
+
+  @override
+  final int exdev = 18;
+}
+
+class _WindowsCodes implements _Codes {
+  const _WindowsCodes();
+
+  @override
+  final int e2big = 7;
+
+  @override
+  final int eacces = 13;
+
+  @override
+  final int eagain = 11;
+
+  @override
+  final int ebadf = 9;
+
+  @override
+  final int ebusy = 16;
+
+  @override
+  final int echild = 10;
+
+  @override
+  final int edeadlk = 36;
+
+  @override
+  final int edom = 33;
+
+  @override
+  final int eexist = 17;
+
+  @override
+  final int efault = 14;
+
+  @override
+  final int efbig = 27;
+
+  @override
+  final int eilseq = 42;
+
+  @override
+  final int eintr = 4;
+
+  @override
+  final int einval = 22;
+
+  @override
+  final int eio = 5;
+
+  @override
+  final int eisdir = 21;
+
+  @override
+  final int eloop = -1;
+
+  @override
+  final int emfile = 24;
+
+  @override
+  final int emlink = 31;
+
+  @override
+  final int enametoolong = 38;
+
+  @override
+  final int enfile = 23;
+
+  @override
+  final int enodev = 19;
+
+  @override
+  final int enoent = 2;
+
+  @override
+  final int enoexec = 8;
+
+  @override
+  final int enolck = 39;
+
+  @override
+  final int enomem = 12;
+
+  @override
+  final int enospc = 28;
+
+  @override
+  final int enosys = 40;
+
+  @override
+  final int enotdir = 20;
+
+  @override
+  final int enotempty = 41;
+
+  @override
+  final int enotty = 25;
+
+  @override
+  final int enxio = 6;
+
+  @override
+  final int eperm = 1;
+
+  @override
+  final int epipe = 32;
+
+  @override
+  final int erange = 34;
+
+  @override
+  final int erofs = 30;
+
+  @override
+  final int espipe = 29;
+
+  @override
+  final int esrch = 3;
+
+  @override
+  final int exdev = 18;
+}
diff --git a/lib/src/interface/error_codes_dart_io.dart b/lib/src/interface/error_codes_dart_io.dart
new file mode 100644
index 0000000..3f0a97f
--- /dev/null
+++ b/lib/src/interface/error_codes_dart_io.dart
@@ -0,0 +1,10 @@
+// Copyright (c) 2017, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'dart:io' show Platform;
+
+/// If we have `dart:io` available, we pull the current operating system from
+/// the [Platform] class, so we'll get errno values that match our current
+/// operating system.
+final String operatingSystem = Platform.operatingSystem;
diff --git a/lib/src/interface/error_codes_internal.dart b/lib/src/interface/error_codes_internal.dart
new file mode 100644
index 0000000..0a9d7dc
--- /dev/null
+++ b/lib/src/interface/error_codes_internal.dart
@@ -0,0 +1,8 @@
+// Copyright (c) 2017, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+/// In environments that don't have `dart:io`, we can't access the Platform
+/// class to determine what platform we're on, so we just pretend we're on
+/// Linux, meaning we'll get errno values that match Linux's errno.h.
+const String operatingSystem = 'linux';
diff --git a/lib/src/interface/file.dart b/lib/src/interface/file.dart
index 5523a78..ce200d5 100644
--- a/lib/src/interface/file.dart
+++ b/lib/src/interface/file.dart
@@ -2,7 +2,11 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-part of file.src.interface;
+import 'dart:async';
+import 'dart:convert';
+
+import 'file_system_entity.dart';
+import '../io.dart' as io;
 
 /// A reference to a file on the file system.
 abstract class File implements FileSystemEntity, io.File {
diff --git a/lib/src/interface/file_system.dart b/lib/src/interface/file_system.dart
index abd954e..084ba82 100644
--- a/lib/src/interface/file_system.dart
+++ b/lib/src/interface/file_system.dart
@@ -2,7 +2,15 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-part of file.src.interface;
+import 'dart:async';
+
+import 'package:path/path.dart' as path;
+
+import 'directory.dart';
+import 'file.dart';
+import 'file_system_entity.dart';
+import 'link.dart';
+import '../io.dart' as io;
 
 /// A generic representation of a file system.
 ///
diff --git a/lib/src/interface/file_system_entity.dart b/lib/src/interface/file_system_entity.dart
index a6152d5..53faa45 100644
--- a/lib/src/interface/file_system_entity.dart
+++ b/lib/src/interface/file_system_entity.dart
@@ -2,7 +2,11 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-part of file.src.interface;
+import 'dart:async';
+
+import 'directory.dart';
+import 'file_system.dart';
+import '../io.dart' as io;
 
 /// The common super class for [File], [Directory], and [Link] objects.
 abstract class FileSystemEntity implements io.FileSystemEntity {
diff --git a/lib/src/interface/link.dart b/lib/src/interface/link.dart
index 261b237..1288363 100644
--- a/lib/src/interface/link.dart
+++ b/lib/src/interface/link.dart
@@ -2,7 +2,10 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-part of file.src.interface;
+import 'dart:async';
+
+import 'file_system_entity.dart';
+import '../io.dart' as io;
 
 /// A reference to a symbolic link on the file system.
 abstract class Link implements FileSystemEntity, io.Link {
diff --git a/lib/src/testing/core_matchers.dart b/lib/src/testing/core_matchers.dart
index b6868e9..502afd1 100644
--- a/lib/src/testing/core_matchers.dart
+++ b/lib/src/testing/core_matchers.dart
@@ -30,31 +30,36 @@ Matcher hasPath(dynamic path) => new _HasPath(path);
 /// Returns a [Matcher] that successfully matches against an instance of
 /// [FileSystemException].
 ///
-/// If [message] is specified, matches will be limited to exceptions with a
-/// matching `message` (either in the exception itself or in the nested
-/// [OSError]).
+/// If [osErrorCode] is specified, matches will be limited to exceptions whose
+/// `osError.errorCode` also match the specified matcher.
 ///
-/// [message] may be a String, a predicate function, or a [Matcher]. If it is
-/// a String, it will be wrapped in an equality matcher.
-Matcher isFileSystemException([dynamic message]) =>
-    new _FileSystemException(message);
+/// [osErrorCode] may be an `int`, a predicate function, or a [Matcher]. If it
+/// is an `int`, it will be wrapped in an equality matcher.
+Matcher isFileSystemException([dynamic osErrorCode]) =>
+    new _FileSystemException(osErrorCode);
 
 /// Returns a matcher that successfully matches against a future or function
 /// that throws a [FileSystemException].
 ///
-/// If [message] is specified, matches will be limited to exceptions with a
-/// matching `message` (either in the exception itself or in the nested
-/// [OSError]).
+/// If [osErrorCode] is specified, matches will be limited to exceptions whose
+/// `osError.errorCode` also match the specified matcher.
 ///
-/// [message] may be a String, a predicate function, or a [Matcher]. If it is
-/// a String, it will be wrapped in an equality matcher.
-Matcher throwsFileSystemException([dynamic message]) =>
-    throwsA(isFileSystemException(message));
+/// [osErrorCode] may be an `int`, a predicate function, or a [Matcher]. If it
+/// is an `int`, it will be wrapped in an equality matcher.
+Matcher throwsFileSystemException([dynamic osErrorCode]) =>
+    throwsA(isFileSystemException(osErrorCode));
 
 /// Expects the specified [callback] to throw a [FileSystemException] with the
-/// specified [message].
-void expectFileSystemException(dynamic message, void callback()) {
-  expect(callback, throwsFileSystemException(message));
+/// specified [osErrorCode] (matched against the exception's
+/// `osError.errorCode`).
+///
+/// [osErrorCode] may be an `int`, a predicate function, or a [Matcher]. If it
+/// is an `int`, it will be wrapped in an equality matcher.
+///
+/// See also:
+///   - [ErrorCodes]
+void expectFileSystemException(dynamic osErrorCode, void callback()) {
+  expect(callback, throwsFileSystemException(osErrorCode));
 }
 
 /// Matcher that successfully matches against a [FileSystemEntity] that
@@ -64,23 +69,26 @@ const Matcher exists = const _Exists();
 class _FileSystemException extends Matcher {
   final Matcher _matcher;
 
-  _FileSystemException(dynamic message)
-      : _matcher = message == null ? null : wrapMatcher(message);
+  _FileSystemException(dynamic osErrorCode)
+      : _matcher = osErrorCode == null ? null : wrapMatcher(osErrorCode);
 
   @override
   bool matches(dynamic item, Map<dynamic, dynamic> matchState) {
     if (item is FileSystemException) {
       return (_matcher == null ||
-          _matcher.matches(item.message, matchState) ||
-          _matcher.matches(item.osError?.message, matchState));
+          _matcher.matches(item.osError?.errorCode, matchState));
     }
     return false;
   }
 
   @override
   Description describe(Description desc) {
-    desc.add('FileSystemException with message: ');
-    return _matcher.describe(desc);
+    if (_matcher == null) {
+      return desc.add('FileSystemException');
+    } else {
+      desc.add('FileSystemException with osError.errorCode: ');
+      return _matcher.describe(desc);
+    }
   }
 }
 
diff --git a/pubspec.yaml b/pubspec.yaml
index 5026759..3001c16 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,5 +1,5 @@
 name: file
-version: 2.1.0
+version: 2.2.0
 authors:
 - Matan Lurey <matanl@google.com>
 - Yegor Jbanov <yjbanov@google.com>
diff --git a/test/chroot_test.dart b/test/chroot_test.dart
index f9e0d62..b911e19 100644
--- a/test/chroot_test.dart
+++ b/test/chroot_test.dart
@@ -104,7 +104,7 @@ void main() {
           test('throwsIfSetToSymlinkToDirectoryOutsideJail', () {
             mem.directory('/bar').createSync();
             mem.link('/tmp/foo').createSync('/bar');
-            expectFileSystemException('No such file or directory', () {
+            expectFileSystemException(ErrorCodes.ENOENT, () {
               fs.currentDirectory = '/foo';
             });
           });
diff --git a/test/common_tests.dart b/test/common_tests.dart
index 206b9c5..86daea2 100644
--- a/test/common_tests.dart
+++ b/test/common_tests.dart
@@ -227,14 +227,14 @@ void runCommonTests(
         });
 
         test('throwsIfSetToNonExistentPath', () {
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.currentDirectory = ns('/foo');
           });
         });
 
         test('throwsIfHasNonExistentPathInComplexChain', () {
           fs.directory(ns('/foo')).createSync();
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.currentDirectory = ns('/bar/../foo');
           });
         });
@@ -295,14 +295,14 @@ void runCommonTests(
 
         test('throwsIfSetToFilePathSegmentAtTail', () {
           fs.file(ns('/foo')).createSync();
-          expectFileSystemException('Not a directory', () {
+          expectFileSystemException(ErrorCodes.ENOTDIR, () {
             fs.currentDirectory = ns('/foo');
           });
         });
 
         test('throwsIfSetToFilePathSegmentViaTraversal', () {
           fs.file(ns('/foo')).createSync();
-          expectFileSystemException('Not a directory', () {
+          expectFileSystemException(ErrorCodes.ENOTDIR, () {
             fs.currentDirectory = ns('/foo/bar/baz');
           });
         });
@@ -325,9 +325,12 @@ void runCommonTests(
         test('throwsIfSetToLinkLoop', () {
           fs.link(ns('/foo')).createSync(ns('/bar'));
           fs.link(ns('/bar')).createSync(ns('/foo'));
-          expectFileSystemException('Too many levels of symbolic links', () {
-            fs.currentDirectory = ns('/foo');
-          });
+          expectFileSystemException(
+            anyOf(ErrorCodes.EMLINK, ErrorCodes.ELOOP),
+            () {
+              fs.currentDirectory = ns('/foo');
+            },
+          );
         });
       });
 
@@ -395,14 +398,14 @@ void runCommonTests(
         });
 
         test('throwsForDifferentPathsToNonExistentEntities', () {
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.identicalSync(ns('/foo'), ns('/bar'));
           });
         });
 
         test('throwsForDifferentPathsToOneFileOneNonExistentEntity', () {
           fs.file(ns('/foo')).createSync();
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.identicalSync(ns('/foo'), ns('/bar'));
           });
         });
@@ -519,10 +522,7 @@ void runCommonTests(
 
         test('throwsIfAlreadyExistsAsFile', () {
           fs.file(ns('/foo')).createSync();
-          // TODO(tvolkert): Change this to just be 'Not a directory'
-          // once Dart 1.22 is stable.
-          String pattern = '(File exists|Not a directory)';
-          expectFileSystemException(matches(pattern), () {
+          expectFileSystemException(ErrorCodes.ENOTDIR, () {
             fs.directory(ns('/foo')).createSync();
           });
         });
@@ -538,22 +538,24 @@ void runCommonTests(
           fs.link(ns('/bar')).createSync(ns('/foo'));
           // TODO(tvolkert): Change this to just be 'Not a directory'
           // once Dart 1.22 is stable.
-          String pattern = '(File exists|Not a directory)';
-          expectFileSystemException(matches(pattern), () {
-            fs.directory(ns('/bar')).createSync();
-          });
+          expectFileSystemException(
+            anyOf(ErrorCodes.EEXIST, ErrorCodes.ENOTDIR),
+            () {
+              fs.directory(ns('/bar')).createSync();
+            },
+          );
         });
 
         test('throwsIfAlreadyExistsAsLinkToNotFoundAtTail', () {
           fs.link(ns('/foo')).createSync(ns('/bar'));
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.directory(ns('/foo')).createSync();
           });
         });
 
         test('throwsIfAlreadyExistsAsLinkToNotFoundViaTraversal', () {
           fs.link(ns('/foo')).createSync(ns('/bar/baz'));
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.directory(ns('/foo')).createSync();
           });
         });
@@ -562,7 +564,7 @@ void runCommonTests(
           fs.directory(ns('/foo')).createSync();
           fs.directory(ns('/bar')).createSync();
           fs.link(ns('/bar/baz')).createSync(ns('/foo/qux'));
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.directory(ns('/bar/baz')).createSync();
           });
         });
@@ -574,7 +576,7 @@ void runCommonTests(
         });
 
         test('throwsIfAncestorDoesntExistRecursiveFalse', () {
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.directory(ns('/foo/bar')).createSync();
           });
         });
@@ -611,14 +613,14 @@ void runCommonTests(
         test('throwsIfDestinationIsFile', () {
           fs.file(ns('/bar')).createSync();
           Directory src = fs.directory(ns('/foo'))..createSync();
-          expectFileSystemException('Not a directory', () {
+          expectFileSystemException(ErrorCodes.ENOTDIR, () {
             src.renameSync(ns('/bar'));
           });
         });
 
         test('throwsIfDestinationParentFolderDoesntExist', () {
           Directory src = fs.directory(ns('/foo'))..createSync();
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             src.renameSync(ns('/bar/baz'));
           });
         });
@@ -627,25 +629,24 @@ void runCommonTests(
           fs.file(ns('/bar/baz')).createSync(recursive: true);
           Directory src = fs.directory(ns('/foo'))..createSync();
           // The error will be 'Directory not empty' on OS X, but it will be
-          // 'File exists' on Linux, so we just ignore it here in the test.
-          expectFileSystemException(null, () {
-            src.renameSync(ns('/bar'));
-          });
+          // 'File exists' on Linux.
+          expectFileSystemException(
+            anyOf(ErrorCodes.ENOTEMPTY, ErrorCodes.EEXIST),
+            () {
+              src.renameSync(ns('/bar'));
+            },
+          );
         });
 
         test('throwsIfSourceDoesntExist', () {
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.directory(ns('/foo')).renameSync(ns('/bar'));
           });
         });
 
         test('throwsIfSourceIsFile', () {
           fs.file(ns('/foo')).createSync();
-          // The error message is usually 'No such file or directory', but
-          // it's occasionally 'Not a directory', 'Directory not empty',
-          // 'File exists', or 'Undefined error'.
-          // https://github.com/dart-lang/sdk/issues/28147
-          expectFileSystemException(null, () {
+          expectFileSystemException(ErrorCodes.ENOTDIR, () {
             fs.directory(ns('/foo')).renameSync(ns('/bar'));
           });
         });
@@ -665,7 +666,7 @@ void runCommonTests(
         test('throwsIfDestinationIsLinkToNotFound', () {
           Directory src = fs.directory(ns('/foo'))..createSync();
           fs.link(ns('/bar')).createSync(ns('/baz'));
-          expectFileSystemException('Not a directory', () {
+          expectFileSystemException(ErrorCodes.ENOTDIR, () {
             src.renameSync(ns('/bar'));
           });
         });
@@ -674,7 +675,7 @@ void runCommonTests(
           Directory src = fs.directory(ns('/foo'))..createSync();
           fs.directory(ns('/bar')).createSync();
           fs.link(ns('/baz')).createSync(ns('/bar'));
-          expectFileSystemException('Not a directory', () {
+          expectFileSystemException(ErrorCodes.ENOTDIR, () {
             src.renameSync(ns('/baz'));
           });
         });
@@ -723,7 +724,7 @@ void runCommonTests(
         test('throwsIfNonEmptyDirectoryExistsAndRecursiveFalse', () {
           Directory dir = fs.directory(ns('/foo'))..createSync();
           fs.file(ns('/foo/bar')).createSync();
-          expectFileSystemException('Directory not empty', () {
+          expectFileSystemException(ErrorCodes.ENOTEMPTY, () {
             dir.deleteSync();
           });
         });
@@ -737,13 +738,13 @@ void runCommonTests(
         });
 
         test('throwsIfDirectoryDoesntExistAndRecursiveFalse', () {
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.directory(ns('/foo')).deleteSync();
           });
         });
 
         test('throwsIfDirectoryDoesntExistAndRecursiveTrue', () {
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.directory(ns('/foo')).deleteSync(recursive: true);
           });
         });
@@ -756,7 +757,7 @@ void runCommonTests(
 
         test('throwsIfPathReferencesFileAndRecursiveFalse', () {
           fs.file(ns('/foo')).createSync();
-          expectFileSystemException('Not a directory', () {
+          expectFileSystemException(ErrorCodes.ENOTDIR, () {
             fs.directory(ns('/foo')).deleteSync();
           });
         });
@@ -804,14 +805,14 @@ void runCommonTests(
         test('throwsIfPathReferencesLinkToFileAndRecursiveFalse', () {
           fs.file(ns('/foo')).createSync();
           fs.link(ns('/bar')).createSync(ns('/foo'));
-          expectFileSystemException('Not a directory', () {
+          expectFileSystemException(ErrorCodes.ENOTDIR, () {
             fs.directory(ns('/bar')).deleteSync();
           });
         });
 
         test('throwsIfPathReferencesLinkToNotFoundAndRecursiveFalse', () {
           fs.link(ns('/foo')).createSync(ns('/bar'));
-          expectFileSystemException('Not a directory', () {
+          expectFileSystemException(ErrorCodes.ENOTDIR, () {
             fs.directory(ns('/foo')).deleteSync();
           });
         });
@@ -826,26 +827,29 @@ void runCommonTests(
           fs.link(ns('/foo')).createSync(ns('/bar'));
           fs.link(ns('/bar')).createSync(ns('/baz'));
           fs.link(ns('/baz'))..createSync(ns('/foo'));
-          expectFileSystemException('Too many levels of symbolic links', () {
-            fs.directory(ns('/foo')).resolveSymbolicLinksSync();
-          });
+          expectFileSystemException(
+            anyOf(ErrorCodes.EMLINK, ErrorCodes.ELOOP),
+            () {
+              fs.directory(ns('/foo')).resolveSymbolicLinksSync();
+            },
+          );
         });
 
         test('throwsIfPathNotFoundInTraversal', () {
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.directory(ns('/foo/bar')).resolveSymbolicLinksSync();
           });
         });
 
         test('throwsIfPathNotFoundAtTail', () {
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.directory(ns('/foo')).resolveSymbolicLinksSync();
           });
         });
 
         test('throwsIfPathNotFoundInMiddleThenBackedOut', () {
           fs.directory(ns('/foo/bar')).createSync(recursive: true);
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.directory(ns('/foo/baz/../bar')).resolveSymbolicLinksSync();
           });
         });
@@ -955,7 +959,7 @@ void runCommonTests(
         });
 
         test('throwsIfDirectoryDoesntExist', () {
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.directory(ns('/foo')).createTempSync();
           });
         });
@@ -985,7 +989,7 @@ void runCommonTests(
 
         test('throwsWithNestedPathPrefixThatDoesntExist', () {
           Directory dir = fs.directory(ns('/foo'))..createSync();
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             dir.createTempSync('bar/baz');
           });
         });
@@ -1019,7 +1023,7 @@ void runCommonTests(
         });
 
         test('throwsIfDirectoryDoesntExist', () {
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.directory(ns('/bar')).listSync();
           });
         });
@@ -1122,7 +1126,7 @@ void runCommonTests(
         });
 
         test('throwsIfAncestorDoesntExistRecursiveFalse', () {
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.file(ns('/foo/bar')).createSync();
           });
         });
@@ -1134,7 +1138,7 @@ void runCommonTests(
 
         test('throwsIfAlreadyExistsAsDirectory', () {
           fs.directory(ns('/foo')).createSync();
-          expectFileSystemException('Is a directory', () {
+          expectFileSystemException(ErrorCodes.EISDIR, () {
             fs.file(ns('/foo')).createSync();
           });
         });
@@ -1142,7 +1146,7 @@ void runCommonTests(
         test('throwsIfAlreadyExistsAsLinkToDirectory', () {
           fs.directory(ns('/foo')).createSync();
           fs.link(ns('/bar')).createSync(ns('/foo'));
-          expectFileSystemException('Is a directory', () {
+          expectFileSystemException(ErrorCodes.EISDIR, () {
             fs.file(ns('/bar')).createSync();
           });
         });
@@ -1165,10 +1169,10 @@ void runCommonTests(
 
         test('throwsIfAlreadyExistsAsLinkToNotFoundViaTraversal', () {
           fs.link(ns('/foo')).createSync(ns('/bar/baz'));
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.file(ns('/foo')).createSync();
           });
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.file(ns('/foo')).createSync(recursive: true);
           });
         });
@@ -1176,7 +1180,7 @@ void runCommonTests(
         /*
         test('throwsIfPathSegmentIsLinkToNotFoundAndRecursiveTrue', () {
           fs.link(ns('/foo')).createSync(ns('/bar'));
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.file(ns('/foo/baz')).createSync(recursive: true);
           });
         });
@@ -1210,7 +1214,7 @@ void runCommonTests(
 
         test('throwsIfDestinationDoesntExistViaTraversal', () {
           File f = fs.file(ns('/foo'))..createSync();
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             f.renameSync(ns('/bar/baz'));
           });
         });
@@ -1226,7 +1230,7 @@ void runCommonTests(
         test('throwsIfDestinationExistsAsDirectory', () {
           File f = fs.file(ns('/foo'))..createSync();
           fs.directory(ns('/bar')).createSync();
-          expectFileSystemException('Is a directory', () {
+          expectFileSystemException(ErrorCodes.EISDIR, () {
             f.renameSync(ns('/bar'));
           });
         });
@@ -1247,7 +1251,7 @@ void runCommonTests(
           File f = fs.file(ns('/foo'))..createSync();
           fs.directory(ns('/bar')).createSync();
           fs.link(ns('/baz')).createSync(ns('/bar'));
-          expectFileSystemException('Is a directory', () {
+          expectFileSystemException(ErrorCodes.EISDIR, () {
             f.renameSync(ns('/baz'));
           });
         });
@@ -1262,14 +1266,14 @@ void runCommonTests(
         });
 
         test('throwsIfSourceDoesntExist', () {
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.file(ns('/foo')).renameSync(ns('/bar'));
           });
         });
 
         test('throwsIfSourceExistsAsDirectory', () {
           fs.directory(ns('/foo')).createSync();
-          expectFileSystemException('Is a directory', () {
+          expectFileSystemException(ErrorCodes.EISDIR, () {
             fs.file(ns('/foo')).renameSync(ns('/bar'));
           });
         });
@@ -1288,14 +1292,14 @@ void runCommonTests(
         test('throwsIfSourceExistsAsLinkToDirectory', () {
           fs.directory(ns('/foo')).createSync();
           fs.link(ns('/bar')).createSync(ns('/foo'));
-          expectFileSystemException('Is a directory', () {
+          expectFileSystemException(ErrorCodes.EISDIR, () {
             fs.file(ns('/bar')).renameSync(ns('/baz'));
           });
         });
 
         test('throwsIfSourceExistsAsLinkToNotFound', () {
           fs.link(ns('/foo')).createSync(ns('/bar'));
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.file(ns('/foo')).renameSync(ns('/baz'));
           });
         });
@@ -1320,7 +1324,7 @@ void runCommonTests(
 
         test('throwsIfDestinationDoesntExistViaTraversal', () {
           File f = fs.file(ns('/foo'))..createSync();
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             f.copySync(ns('/bar/baz'));
           });
         });
@@ -1342,7 +1346,7 @@ void runCommonTests(
         test('throwsIfDestinationExistsAsDirectory', () {
           File f = fs.file(ns('/foo'))..createSync();
           fs.directory(ns('/bar')).createSync();
-          expectFileSystemException('Is a directory', () {
+          expectFileSystemException(ErrorCodes.EISDIR, () {
             f.copySync(ns('/bar'));
           });
         });
@@ -1370,20 +1374,20 @@ void runCommonTests(
           File f = fs.file(ns('/foo'))..createSync();
           fs.directory(ns('/bar')).createSync();
           fs.link(ns('/baz')).createSync(ns('/bar'));
-          expectFileSystemException('Is a directory', () {
+          expectFileSystemException(ErrorCodes.EISDIR, () {
             f.copySync(ns('/baz'));
           });
         });
 
         test('throwsIfSourceDoesntExist', () {
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.file(ns('/foo')).copySync(ns('/bar'));
           });
         });
 
         test('throwsIfSourceExistsAsDirectory', () {
           fs.directory(ns('/foo')).createSync();
-          expectFileSystemException('Is a directory', () {
+          expectFileSystemException(ErrorCodes.EISDIR, () {
             fs.file(ns('/foo')).copySync(ns('/bar'));
           });
         });
@@ -1454,14 +1458,14 @@ void runCommonTests(
 
       group('length', () {
         test('throwsIfDoesntExist', () {
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.file(ns('/foo')).lengthSync();
           });
         });
 
         test('throwsIfExistsAsDirectory', () {
           fs.directory(ns('/foo')).createSync();
-          expectFileSystemException('Is a directory', () {
+          expectFileSystemException(ErrorCodes.EISDIR, () {
             fs.file(ns('/foo')).lengthSync();
           });
         });
@@ -1505,14 +1509,14 @@ void runCommonTests(
         });
 
         test('throwsIfDoesntExist', () {
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.file(ns('/foo')).lastAccessedSync();
           });
         });
 
         test('throwsIfExistsAsDirectory', () {
           fs.directory(ns('/foo')).createSync();
-          expectFileSystemException('Is a directory', () {
+          expectFileSystemException(ErrorCodes.EISDIR, () {
             fs.file(ns('/foo')).lastAccessedSync();
           });
         });
@@ -1532,14 +1536,14 @@ void runCommonTests(
         final DateTime time = new DateTime(1999);
 
         test('throwsIfDoesntExist', () {
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.file(ns('/foo')).setLastAccessedSync(time);
           });
         });
 
         test('throwsIfExistsAsDirectory', () {
           fs.directory(ns('/foo')).createSync();
-          expectFileSystemException('Is a directory', () {
+          expectFileSystemException(ErrorCodes.EISDIR, () {
             fs.file(ns('/foo')).setLastAccessedSync(time);
           });
         });
@@ -1569,14 +1573,14 @@ void runCommonTests(
         });
 
         test('throwsIfDoesntExist', () {
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.file(ns('/foo')).lastModifiedSync();
           });
         });
 
         test('throwsIfExistsAsDirectory', () {
           fs.directory(ns('/foo')).createSync();
-          expectFileSystemException('Is a directory', () {
+          expectFileSystemException(ErrorCodes.EISDIR, () {
             fs.file(ns('/foo')).lastModifiedSync();
           });
         });
@@ -1596,14 +1600,14 @@ void runCommonTests(
         final DateTime time = new DateTime(1999);
 
         test('throwsIfDoesntExist', () {
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.file(ns('/foo')).setLastModifiedSync(time);
           });
         });
 
         test('throwsIfExistsAsDirectory', () {
           fs.directory(ns('/foo')).createSync();
-          expectFileSystemException('Is a directory', () {
+          expectFileSystemException(ErrorCodes.EISDIR, () {
             fs.file(ns('/foo')).setLastModifiedSync(time);
           });
         });
@@ -1626,7 +1630,7 @@ void runCommonTests(
         void testIfDoesntExistAtTail(FileMode mode) {
           if (mode == FileMode.READ) {
             test('throwsIfDoesntExistAtTail', () {
-              expectFileSystemException('No such file or directory', () {
+              expectFileSystemException(ErrorCodes.ENOENT, () {
                 fs.file(ns('/bar')).openSync(mode: mode);
               });
             });
@@ -1641,7 +1645,7 @@ void runCommonTests(
 
         void testThrowsIfDoesntExistViaTraversal(FileMode mode) {
           test('throwsIfDoesntExistViaTraversal', () {
-            expectFileSystemException('No such file or directory', () {
+            expectFileSystemException(ErrorCodes.ENOENT, () {
               fs.file(ns('/bar/baz')).openSync(mode: mode);
             });
           });
@@ -1668,28 +1672,28 @@ void runCommonTests(
 
             test('succeedsIfClosedAfterClosed', () {
               raf.closeSync();
-              expectFileSystemException('File closed', () {
+              expectFileSystemException(null, () {
                 raf.closeSync();
               });
             });
 
             test('throwsIfReadAfterClose', () {
               raf.closeSync();
-              expectFileSystemException('File closed', () {
+              expectFileSystemException(null, () {
                 raf.readByteSync();
               });
             });
 
             test('throwsIfWriteAfterClose', () {
               raf.closeSync();
-              expectFileSystemException('File closed', () {
+              expectFileSystemException(null, () {
                 raf.writeByteSync(0xBAD);
               });
             });
 
             test('throwsIfTruncateAfterClose', () {
               raf.closeSync();
-              expectFileSystemException('File closed', () {
+              expectFileSystemException(null, () {
                 raf.truncateSync(0);
               });
             });
@@ -1707,19 +1711,19 @@ void runCommonTests(
             if (mode == FileMode.WRITE_ONLY ||
                 mode == FileMode.WRITE_ONLY_APPEND) {
               test('throwsIfReadByte', () {
-                expectFileSystemException('Bad file descriptor', () {
+                expectFileSystemException(ErrorCodes.EBADF, () {
                   raf.readByteSync();
                 });
               });
 
               test('throwsIfRead', () {
-                expectFileSystemException('Bad file descriptor', () {
+                expectFileSystemException(ErrorCodes.EBADF, () {
                   raf.readSync(2);
                 });
               });
 
               test('throwsIfReadInto', () {
-                expectFileSystemException('Bad file descriptor', () {
+                expectFileSystemException(ErrorCodes.EBADF, () {
                   raf.readIntoSync(new List<int>(5));
                 });
               });
@@ -1777,19 +1781,19 @@ void runCommonTests(
 
             if (mode == FileMode.READ) {
               test('throwsIfWriteByte', () {
-                expectFileSystemException('Bad file descriptor', () {
+                expectFileSystemException(ErrorCodes.EBADF, () {
                   raf.writeByteSync(0xBAD);
                 });
               });
 
               test('throwsIfWriteFrom', () {
-                expectFileSystemException('Bad file descriptor', () {
+                expectFileSystemException(ErrorCodes.EBADF, () {
                   raf.writeFromSync(<int>[1, 2, 3, 4]);
                 });
               });
 
               test('throwsIfWriteString', () {
-                expectFileSystemException('Bad file descriptor', () {
+                expectFileSystemException(ErrorCodes.EBADF, () {
                   raf.writeStringSync('This should throw.');
                 });
               });
@@ -1927,7 +1931,7 @@ void runCommonTests(
               }
 
               test('throwsIfSetToNegativeNumber', () {
-                expectFileSystemException('Invalid argument', () {
+                expectFileSystemException(ErrorCodes.EINVAL, () {
                   raf.setPositionSync(-12);
                 });
               });
@@ -1935,7 +1939,7 @@ void runCommonTests(
 
             if (mode == FileMode.READ) {
               test('throwsIfTruncate', () {
-                expectFileSystemException('Invalid argument', () {
+                expectFileSystemException(ErrorCodes.EINVAL, () {
                   raf.truncateSync(5);
                 });
               });
@@ -1963,7 +1967,7 @@ void runCommonTests(
                 });
 
                 test('throwsIfSetToNegativeNumber', () {
-                  expectFileSystemException('Invalid argument', () {
+                  expectFileSystemException(ErrorCodes.EINVAL, () {
                     raf.truncateSync(-2);
                   });
                 });
@@ -1999,8 +2003,7 @@ void runCommonTests(
       group('openRead', () {
         test('throwsIfDoesntExist', () {
           Stream<List<int>> stream = fs.file(ns('/foo')).openRead();
-          expect(stream.drain(),
-              throwsFileSystemException('No such file or directory'));
+          expect(stream.drain(), throwsFileSystemException(ErrorCodes.ENOENT));
         });
 
         test('succeedsIfExistsAsFile', () async {
@@ -2015,7 +2018,7 @@ void runCommonTests(
         test('throwsIfExistsAsDirectory', () {
           fs.directory(ns('/foo')).createSync();
           Stream<List<int>> stream = fs.file(ns('/foo')).openRead();
-          expect(stream.drain(), throwsFileSystemException('Is a directory'));
+          expect(stream.drain(), throwsFileSystemException(ErrorCodes.EISDIR));
         });
 
         test('succeedsIfExistsAsLinkToFile', () async {
@@ -2074,14 +2077,14 @@ void runCommonTests(
         test('throwsIfExistsAsDirectory', () {
           fs.directory(ns('/foo')).createSync();
           expect(fs.file(ns('/foo')).openWrite().close(),
-              throwsFileSystemException('Is a directory'));
+              throwsFileSystemException(ErrorCodes.EISDIR));
         });
 
         test('throwsIfExistsAsLinkToDirectory', () {
           fs.directory(ns('/foo')).createSync();
           fs.link(ns('/bar')).createSync(ns('/foo'));
           expect(fs.file(ns('/bar')).openWrite().close(),
-              throwsFileSystemException('Is a directory'));
+              throwsFileSystemException(ErrorCodes.EISDIR));
         });
 
         test('throwsIfModeIsRead', () {
@@ -2281,14 +2284,14 @@ void runCommonTests(
 
       group('readAsBytes', () {
         test('throwsIfDoesntExist', () {
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.file(ns('/foo')).readAsBytesSync();
           });
         });
 
         test('throwsIfExistsAsDirectory', () {
           fs.directory(ns('/foo')).createSync();
-          expectFileSystemException('Is a directory', () {
+          expectFileSystemException(ErrorCodes.EISDIR, () {
             fs.file(ns('/foo')).readAsBytesSync();
           });
         });
@@ -2296,7 +2299,7 @@ void runCommonTests(
         test('throwsIfExistsAsLinkToDirectory', () {
           fs.directory(ns('/foo')).createSync();
           fs.link(ns('/bar')).createSync(ns('/foo'));
-          expectFileSystemException('Is a directory', () {
+          expectFileSystemException(ErrorCodes.EISDIR, () {
             fs.file(ns('/bar')).readAsBytesSync();
           });
         });
@@ -2322,14 +2325,14 @@ void runCommonTests(
 
       group('readAsString', () {
         test('throwsIfDoesntExist', () {
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.file(ns('/foo')).readAsStringSync();
           });
         });
 
         test('throwsIfExistsAsDirectory', () {
           fs.directory(ns('/foo')).createSync();
-          expectFileSystemException('Is a directory', () {
+          expectFileSystemException(ErrorCodes.EISDIR, () {
             fs.file(ns('/foo')).readAsStringSync();
           });
         });
@@ -2337,7 +2340,7 @@ void runCommonTests(
         test('throwsIfExistsAsLinkToDirectory', () {
           fs.directory(ns('/foo')).createSync();
           fs.link(ns('/bar')).createSync(ns('/foo'));
-          expectFileSystemException('Is a directory', () {
+          expectFileSystemException(ErrorCodes.EISDIR, () {
             fs.file(ns('/bar')).readAsStringSync();
           });
         });
@@ -2370,14 +2373,14 @@ void runCommonTests(
 
       group('readAsLines', () {
         test('throwsIfDoesntExist', () {
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.file(ns('/foo')).readAsLinesSync();
           });
         });
 
         test('throwsIfExistsAsDirectory', () {
           fs.directory(ns('/foo')).createSync();
-          expectFileSystemException('Is a directory', () {
+          expectFileSystemException(ErrorCodes.EISDIR, () {
             fs.file(ns('/foo')).readAsLinesSync();
           });
         });
@@ -2385,7 +2388,7 @@ void runCommonTests(
         test('throwsIfExistsAsLinkToDirectory', () {
           fs.directory(ns('/foo')).createSync();
           fs.link(ns('/bar')).createSync(ns('/foo'));
-          expectFileSystemException('Is a directory', () {
+          expectFileSystemException(ErrorCodes.EISDIR, () {
             fs.file(ns('/bar')).readAsLinesSync();
           });
         });
@@ -2431,7 +2434,7 @@ void runCommonTests(
 
         test('throwsIfExistsAsDirectory', () {
           fs.directory(ns('/foo')).createSync();
-          expectFileSystemException('Is a directory', () {
+          expectFileSystemException(ErrorCodes.EISDIR, () {
             fs.file(ns('/foo')).writeAsBytesSync(<int>[1, 2, 3, 4]);
           });
         });
@@ -2439,7 +2442,7 @@ void runCommonTests(
         test('throwsIfExistsAsLinkToDirectory', () {
           fs.directory(ns('/foo')).createSync();
           fs.link(ns('/bar')).createSync(ns('/foo'));
-          expectFileSystemException('Is a directory', () {
+          expectFileSystemException(ErrorCodes.EISDIR, () {
             fs.file(ns('/foo')).writeAsBytesSync(<int>[1, 2, 3, 4]);
           });
         });
@@ -2453,7 +2456,7 @@ void runCommonTests(
 
         test('throwsIfFileModeRead', () {
           File f = fs.file(ns('/foo'))..createSync();
-          expectFileSystemException('Bad file descriptor', () {
+          expectFileSystemException(ErrorCodes.EBADF, () {
             f.writeAsBytesSync(<int>[1], mode: FileMode.READ);
           });
         });
@@ -2495,7 +2498,7 @@ void runCommonTests(
 
         test('throwsIfExistsAsDirectory', () {
           fs.directory(ns('/foo')).createSync();
-          expectFileSystemException('Is a directory', () {
+          expectFileSystemException(ErrorCodes.EISDIR, () {
             fs.file(ns('/foo')).writeAsStringSync('Hello world');
           });
         });
@@ -2503,7 +2506,7 @@ void runCommonTests(
         test('throwsIfExistsAsLinkToDirectory', () {
           fs.directory(ns('/foo')).createSync();
           fs.link(ns('/bar')).createSync(ns('/foo'));
-          expectFileSystemException('Is a directory', () {
+          expectFileSystemException(ErrorCodes.EISDIR, () {
             fs.file(ns('/foo')).writeAsStringSync('Hello world');
           });
         });
@@ -2517,7 +2520,7 @@ void runCommonTests(
 
         test('throwsIfFileModeRead', () {
           File f = fs.file(ns('/foo'))..createSync();
-          expectFileSystemException('Bad file descriptor', () {
+          expectFileSystemException(ErrorCodes.EBADF, () {
             f.writeAsStringSync('Hello world', mode: FileMode.READ);
           });
         });
@@ -2633,13 +2636,13 @@ void runCommonTests(
         });
 
         test('throwsIfDoesntExistAndRecursiveFalse', () {
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.file(ns('/foo')).deleteSync();
           });
         });
 
         test('throwsIfDoesntExistAndRecursiveTrue', () {
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.file(ns('/foo')).deleteSync(recursive: true);
           });
         });
@@ -2652,7 +2655,7 @@ void runCommonTests(
 
         test('throwsIfExistsAsDirectoryAndRecursiveFalse', () {
           fs.directory(ns('/foo')).createSync();
-          expectFileSystemException('Is a directory', () {
+          expectFileSystemException(ErrorCodes.EISDIR, () {
             fs.file(ns('/foo')).deleteSync();
           });
         });
@@ -2685,7 +2688,7 @@ void runCommonTests(
         test('throwsIfExistsAsLinkToDirectoryAndRecursiveFalse', () {
           fs.directory(ns('/foo')).createSync();
           fs.link(ns('/bar')).createSync(ns('/foo'));
-          expectFileSystemException('Is a directory', () {
+          expectFileSystemException(ErrorCodes.EISDIR, () {
             fs.file(ns('/bar')).deleteSync();
           });
         });
@@ -2816,20 +2819,20 @@ void runCommonTests(
         });
 
         test('throwsIfLinkDoesntExistAtTail', () {
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.link(ns('/foo')).deleteSync();
           });
         });
 
         test('throwsIfLinkDoesntExistViaTraversal', () {
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.link(ns('/foo/bar')).deleteSync();
           });
         });
 
         test('throwsIfPathReferencesFileAndRecursiveFalse', () {
           fs.file(ns('/foo')).createSync();
-          expectFileSystemException('Invalid argument', () {
+          expectFileSystemException(ErrorCodes.EINVAL, () {
             fs.link(ns('/foo')).deleteSync();
           });
         });
@@ -2845,10 +2848,12 @@ void runCommonTests(
           fs.directory(ns('/foo')).createSync();
           // TODO(tvolkert): Change this to just be 'Is a directory'
           // once Dart 1.22 is stable.
-          String pattern = '(Invalid argument|Is a directory)';
-          expectFileSystemException(matches(pattern), () {
-            fs.link(ns('/foo')).deleteSync();
-          });
+          expectFileSystemException(
+            anyOf(ErrorCodes.EINVAL, ErrorCodes.EISDIR),
+            () {
+              fs.link(ns('/foo')).deleteSync();
+            },
+          );
         });
 
         test('succeedsIfPathReferencesDirectoryAndRecursiveTrue', () {
@@ -2938,7 +2943,7 @@ void runCommonTests(
         });
 
         test('throwsIfLinkDoesntExistViaTraversalAndRecursiveFalse', () {
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.link(ns('/foo/bar')).createSync('baz');
           });
         });
@@ -2954,28 +2959,28 @@ void runCommonTests(
 
         test('throwsIfAlreadyExistsAsFile', () {
           fs.file(ns('/foo')).createSync();
-          expectFileSystemException('File exists', () {
+          expectFileSystemException(ErrorCodes.EEXIST, () {
             fs.link(ns('/foo')).createSync(ns('/bar'));
           });
         });
 
         test('throwsIfAlreadyExistsAsDirectory', () {
           fs.directory(ns('/foo')).createSync();
-          expectFileSystemException('File exists', () {
+          expectFileSystemException(ErrorCodes.EEXIST, () {
             fs.link(ns('/foo')).createSync(ns('/bar'));
           });
         });
 
         test('throwsIfAlreadyExistsWithSameTarget', () {
           fs.link(ns('/foo')).createSync(ns('/bar'));
-          expectFileSystemException('File exists', () {
+          expectFileSystemException(ErrorCodes.EEXIST, () {
             fs.link(ns('/foo')).createSync(ns('/bar'));
           });
         });
 
         test('throwsIfAlreadyExistsWithDifferentTarget', () {
           fs.link(ns('/foo')).createSync(ns('/bar'));
-          expectFileSystemException('File exists', () {
+          expectFileSystemException(ErrorCodes.EEXIST, () {
             fs.link(ns('/foo')).createSync(ns('/baz'));
           });
         });
@@ -2988,20 +2993,20 @@ void runCommonTests(
         });
 
         test('throwsIfLinkDoesntExistAtTail', () {
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.link(ns('/foo')).updateSync(ns('/bar'));
           });
         });
 
         test('throwsIfLinkDoesntExistViaTraversal', () {
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.link(ns('/foo/bar')).updateSync(ns('/baz'));
           });
         });
 
         test('throwsIfPathReferencesFile', () {
           fs.file(ns('/foo')).createSync();
-          expectFileSystemException('Invalid argument', () {
+          expectFileSystemException(ErrorCodes.EINVAL, () {
             fs.link(ns('/foo')).updateSync(ns('/bar'));
           });
         });
@@ -3010,10 +3015,12 @@ void runCommonTests(
           fs.directory(ns('/foo')).createSync();
           // TODO(tvolkert): Change this to just be 'Is a directory'
           // once Dart 1.22 is stable.
-          String pattern = '(Invalid argument|Is a directory)';
-          expectFileSystemException(matches(pattern), () {
-            fs.link(ns('/foo')).updateSync(ns('/bar'));
-          });
+          expectFileSystemException(
+            anyOf(ErrorCodes.EINVAL, ErrorCodes.EISDIR),
+            () {
+              fs.link(ns('/foo')).updateSync(ns('/bar'));
+            },
+          );
         });
 
         test('succeedsIfNewTargetSameAsOldTarget', () {
@@ -3049,27 +3056,27 @@ void runCommonTests(
 
       group('target', () {
         test('throwsIfLinkDoesntExistAtTail', () {
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.link(ns('/foo')).targetSync();
           });
         });
 
         test('throwsIfLinkDoesntExistViaTraversal', () {
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.link(ns('/foo/bar')).targetSync();
           });
         });
 
         test('throwsIfPathReferencesFile', () {
           fs.file(ns('/foo')).createSync();
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.link(ns('/foo')).targetSync();
           });
         });
 
         test('throwsIfPathReferencesDirectory', () {
           fs.directory(ns('/foo')).createSync();
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.link(ns('/foo')).targetSync();
           });
         });
@@ -3106,27 +3113,27 @@ void runCommonTests(
         });
 
         test('throwsIfSourceDoesntExistAtTail', () {
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.link(ns('/foo')).renameSync(ns('/bar'));
           });
         });
 
         test('throwsIfSourceDoesntExistViaTraversal', () {
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             fs.link(ns('/foo/bar')).renameSync(ns('/bar'));
           });
         });
 
         test('throwsIfSourceIsFile', () {
           fs.file(ns('/foo')).createSync();
-          expectFileSystemException('Invalid argument', () {
+          expectFileSystemException(ErrorCodes.EINVAL, () {
             fs.link(ns('/foo')).renameSync(ns('/bar'));
           });
         });
 
         test('throwsIfSourceIsDirectory', () {
           fs.directory(ns('/foo')).createSync();
-          expectFileSystemException('Is a directory', () {
+          expectFileSystemException(ErrorCodes.EISDIR, () {
             fs.link(ns('/foo')).renameSync(ns('/bar'));
           });
         });
@@ -3189,7 +3196,7 @@ void runCommonTests(
 
         test('throwsIfDestinationDoesntExistViaTraversal', () {
           Link l = fs.link(ns('/foo'))..createSync(ns('/bar'));
-          expectFileSystemException('No such file or directory', () {
+          expectFileSystemException(ErrorCodes.ENOENT, () {
             l.renameSync(ns('/baz/qux'));
           });
         });
@@ -3197,7 +3204,7 @@ void runCommonTests(
         test('throwsIfDestinationExistsAsFile', () {
           Link l = fs.link(ns('/foo'))..createSync(ns('/bar'));
           fs.file(ns('/baz')).createSync();
-          expectFileSystemException('Invalid argument', () {
+          expectFileSystemException(ErrorCodes.EINVAL, () {
             l.renameSync(ns('/baz'));
           });
         });
@@ -3205,7 +3212,7 @@ void runCommonTests(
         test('throwsIfDestinationExistsAsDirectory', () {
           Link l = fs.link(ns('/foo'))..createSync(ns('/bar'));
           fs.directory(ns('/baz')).createSync();
-          expectFileSystemException('Invalid argument', () {
+          expectFileSystemException(ErrorCodes.EINVAL, () {
             l.renameSync(ns('/baz'));
           });
         });