FileStat interface

interface class FileStat

The result of calling the POSIX stat() function on a file system object.

This is an immutable object, representing the snapshotted values returned by the stat() call.

Properties

accessed final

final DateTime accessed

The time of the last access to the data of the file system object.

On Windows platforms, this may have 1 day granularity, and be out of date by an hour.

Implementation

final DateTime accessed;

changed final

final DateTime changed

The time of the last change to the data or metadata of the file system object.

On Windows platforms, this is instead the file creation time.

Implementation

final DateTime changed;

hashCode no setter inherited

int get hashCode

The hash code for this object.

A hash code is a single integer which represents the state of the object that affects operator == comparisons.

All objects have hash codes. The default hash code implemented by Object represents only the identity of the object, the same way as the default operator == implementation only considers objects equal if they are identical (see identityHashCode).

If operator == is overridden to use the object state instead, the hash code must also be changed to represent that state, otherwise the object cannot be used in hash based data structures like the default Set and Map implementations.

Hash codes must be the same for objects that are equal to each other according to operator ==. The hash code of an object should only change if the object changes in a way that affects equality. There are no further requirements for the hash codes. They need not be consistent between executions of the same program and there are no distribution guarantees.

Objects that are not equal are allowed to have the same hash code. It is even technically allowed that all instances have the same hash code, but if clashes happen too often, it may reduce the efficiency of hash-based data structures like HashSet or HashMap.

If a subclass overrides hashCode, it should override the operator == operator as well to maintain consistency.

Inherited from Object.

Implementation

external int get hashCode;

mode final

final int mode

The mode of the file system object.

Permissions are encoded in the lower 16 bits of this number, and can be decoded using the modeString getter.

Implementation

final int mode;

modified final

final DateTime modified

The time of the last change to the data of the file system object.

Implementation

final DateTime modified;

runtimeType no setter inherited

Type get runtimeType

A representation of the runtime type of the object.

Inherited from Object.

Implementation

external Type get runtimeType;

size final

final int size

The size of the file system object.

Implementation

final int size;

type final

final FileSystemEntityType type

The type of the underlying file system object.

FileSystemEntityType.notFound if stat or statSync failed.

Implementation

final FileSystemEntityType type;

Methods

modeString()

String modeString()

The mode value as a human-readable string.

The string is in the format "rwxrwxrwx", reflecting the user, group, and world permissions to read, write, and execute the file system object, with "-" replacing the letter for missing permissions. Extra permission bits may be represented by prepending "(suid)", "(guid)", and/or "(sticky)" to the mode string.

Implementation

String modeString() {
  var permissions = mode & 0xFFF;
  var codes = const ['---', '--x', '-w-', '-wx', 'r--', 'r-x', 'rw-', 'rwx'];
  var result = [];
  if ((permissions & 0x800) != 0) result.add("(suid) ");
  if ((permissions & 0x400) != 0) result.add("(guid) ");
  if ((permissions & 0x200) != 0) result.add("(sticky) ");
  result
    ..add(codes[(permissions >> 6) & 0x7])
    ..add(codes[(permissions >> 3) & 0x7])
    ..add(codes[permissions & 0x7]);
  return result.join();
}

noSuchMethod() inherited

dynamic noSuchMethod(Invocation invocation)

Invoked when a nonexistent method or property is accessed.

A dynamic member invocation can attempt to call a member which doesn't exist on the receiving object. Example:

dynamic object = 1;
object.add(42); // Statically allowed, run-time error

This invalid code will invoke the noSuchMethod method of the integer 1 with an Invocation representing the .add(42) call and arguments (which then throws).

Classes can override noSuchMethod to provide custom behavior for such invalid dynamic invocations.

A class with a non-default noSuchMethod invocation can also omit implementations for members of its interface. Example:

class MockList<T> implements List<T> {
  noSuchMethod(Invocation invocation) {
    log(invocation);
    super.noSuchMethod(invocation); // Will throw.
  }
}
void main() {
  MockList().add(42);
}

This code has no compile-time warnings or errors even though the MockList class has no concrete implementation of any of the List interface methods. Calls to List methods are forwarded to noSuchMethod, so this code will log an invocation similar to Invocation.method(#add, [42]) and then throw.

If a value is returned from noSuchMethod, it becomes the result of the original invocation. If the value is not of a type that can be returned by the original invocation, a type error occurs at the invocation.

The default behavior is to throw a NoSuchMethodError.

Inherited from Object.

Implementation

@pragma("vm:entry-point")
@pragma("wasm:entry-point")
external dynamic noSuchMethod(Invocation invocation);

toString() override

String toString()

A string representation of this object.

Some classes have a default textual representation, often paired with a static parse function (like int.parse). These classes will provide the textual representation as their string representation.

Other classes have no meaningful textual representation that a program will care about. Such classes will typically override toString to provide useful information when inspecting the object, mainly for debugging or logging.

Implementation

String toString() =>
    """
FileStat: type $type
        changed $changed
        modified $modified
        accessed $accessed
        mode ${modeString()}
        size $size""";

Operators

operator ==() inherited

bool operator ==(Object other)

The equality operator.

The default behavior for all Objects is to return true if and only if this object and other are the same object.

Override this method to specify a different equality relation on a class. The overriding method must still be an equivalence relation. That is, it must be:

• Total: It must return a boolean for all arguments. It should never throw.

• Reflexive: For all objects o, o == o must be true.

• Symmetric: For all objects o1 and o2, o1 == o2 and o2 == o1 must either both be true, or both be false.

• Transitive: For all objects o1, o2, and o3, if o1 == o2 and o2 == o3 are true, then o1 == o3 must be true.

The method should also be consistent over time, so whether two objects are equal should only change if at least one of the objects was modified.

If a subclass overrides the equality operator, it should override the hashCode method as well to maintain consistency.

Inherited from Object.

Implementation

external bool operator ==(Object other);

Static Methods

stat()

Future<FileStat> stat(String path)

Asynchronously calls the operating system's stat() function (or equivalent) on path.

If path is a symbolic link then it is resolved and results for the resulting file are returned.

Returns a Future which completes with the same results as statSync.

Implementation

static Future<FileStat> stat(String path) {
  final IOOverrides? overrides = IOOverrides.current;
  if (overrides == null) {
    return _stat(path);
  }
  return overrides.stat(path);
}

statSync()

FileStat statSync(String path)

Calls the operating system's stat() function (or equivalent) on path.

If path is a symbolic link then it is resolved and results for the resulting file are returned.

Returns a FileStat object containing the data returned by stat(). If the call fails, returns a FileStat object with FileStat.type set to FileSystemEntityType.notFound and the other fields invalid.

Implementation

static FileStat statSync(String path) {
  final IOOverrides? overrides = IOOverrides.current;
  if (overrides == null) {
    return _statSyncInternal(path);
  }
  return overrides.statSync(path);
}