1 // ignore-tidy-filelength
3 //! Filesystem manipulation operations.
5 //! This module contains basic methods to manipulate the contents of the local
6 //! filesystem. All methods in this module represent cross-platform filesystem
7 //! operations. Extra platform-specific functionality can be found in the
8 //! extension traits of `std::os::$platform`.
10 #![stable(feature = "rust1", since = "1.0.0")]
12 use crate::ffi::OsString;
14 use crate::io::{self, Initializer, IoSlice, IoSliceMut, Read, Seek, SeekFrom, Write};
15 use crate::path::{Path, PathBuf};
16 use crate::sys::fs as fs_imp;
17 use crate::sys_common::{AsInner, AsInnerMut, FromInner, IntoInner};
18 use crate::time::SystemTime;
20 /// A reference to an open file on the filesystem.
22 /// An instance of a `File` can be read and/or written depending on what options
23 /// it was opened with. Files also implement [`Seek`] to alter the logical cursor
24 /// that the file contains internally.
26 /// Files are automatically closed when they go out of scope. Errors detected
27 /// on closing are ignored by the implementation of `Drop`. Use the method
28 /// [`sync_all`] if these errors must be manually handled.
32 /// Creates a new file and write bytes to it (you can also use [`write`]):
35 /// use std::fs::File;
36 /// use std::io::prelude::*;
38 /// fn main() -> std::io::Result<()> {
39 /// let mut file = File::create("foo.txt")?;
40 /// file.write_all(b"Hello, world!")?;
45 /// Read the contents of a file into a [`String`] (you can also use [`read`]):
48 /// use std::fs::File;
49 /// use std::io::prelude::*;
51 /// fn main() -> std::io::Result<()> {
52 /// let mut file = File::open("foo.txt")?;
53 /// let mut contents = String::new();
54 /// file.read_to_string(&mut contents)?;
55 /// assert_eq!(contents, "Hello, world!");
60 /// It can be more efficient to read the contents of a file with a buffered
61 /// [`Read`]er. This can be accomplished with [`BufReader<R>`]:
64 /// use std::fs::File;
65 /// use std::io::BufReader;
66 /// use std::io::prelude::*;
68 /// fn main() -> std::io::Result<()> {
69 /// let file = File::open("foo.txt")?;
70 /// let mut buf_reader = BufReader::new(file);
71 /// let mut contents = String::new();
72 /// buf_reader.read_to_string(&mut contents)?;
73 /// assert_eq!(contents, "Hello, world!");
78 /// Note that, although read and write methods require a `&mut File`, because
79 /// of the interfaces for [`Read`] and [`Write`], the holder of a `&File` can
80 /// still modify the file, either through methods that take `&File` or by
81 /// retrieving the underlying OS object and modifying the file that way.
82 /// Additionally, many operating systems allow concurrent modification of files
83 /// by different processes. Avoid assuming that holding a `&File` means that the
84 /// file will not change.
86 /// [`Seek`]: ../io/trait.Seek.html
87 /// [`String`]: ../string/struct.String.html
88 /// [`Read`]: ../io/trait.Read.html
89 /// [`Write`]: ../io/trait.Write.html
90 /// [`BufReader<R>`]: ../io/struct.BufReader.html
91 /// [`sync_all`]: struct.File.html#method.sync_all
92 /// [`read`]: fn.read.html
93 /// [`write`]: fn.write.html
94 #[stable(feature = "rust1", since = "1.0.0")]
99 /// Metadata information about a file.
101 /// This structure is returned from the [`metadata`] or
102 /// [`symlink_metadata`] function or method and represents known
103 /// metadata about a file such as its permissions, size, modification
106 /// [`metadata`]: fn.metadata.html
107 /// [`symlink_metadata`]: fn.symlink_metadata.html
108 #[stable(feature = "rust1", since = "1.0.0")]
110 pub struct Metadata(fs_imp::FileAttr);
112 /// Iterator over the entries in a directory.
114 /// This iterator is returned from the [`read_dir`] function of this module and
115 /// will yield instances of [`io::Result`]`<`[`DirEntry`]`>`. Through a [`DirEntry`]
116 /// information like the entry's path and possibly other metadata can be
119 /// The order in which this iterator returns entries is platform and filesystem
124 /// This [`io::Result`] will be an [`Err`] if there's some sort of intermittent
125 /// IO error during iteration.
127 /// [`read_dir`]: fn.read_dir.html
128 /// [`DirEntry`]: struct.DirEntry.html
129 /// [`io::Result`]: ../io/type.Result.html
130 /// [`Err`]: ../result/enum.Result.html#variant.Err
131 #[stable(feature = "rust1", since = "1.0.0")]
133 pub struct ReadDir(fs_imp::ReadDir);
135 /// Entries returned by the [`ReadDir`] iterator.
137 /// [`ReadDir`]: struct.ReadDir.html
139 /// An instance of `DirEntry` represents an entry inside of a directory on the
140 /// filesystem. Each entry can be inspected via methods to learn about the full
141 /// path or possibly other metadata through per-platform extension traits.
142 #[stable(feature = "rust1", since = "1.0.0")]
143 pub struct DirEntry(fs_imp::DirEntry);
145 /// Options and flags which can be used to configure how a file is opened.
147 /// This builder exposes the ability to configure how a [`File`] is opened and
148 /// what operations are permitted on the open file. The [`File::open`] and
149 /// [`File::create`] methods are aliases for commonly used options using this
152 /// [`File`]: struct.File.html
153 /// [`File::open`]: struct.File.html#method.open
154 /// [`File::create`]: struct.File.html#method.create
156 /// Generally speaking, when using `OpenOptions`, you'll first call [`new`],
157 /// then chain calls to methods to set each option, then call [`open`],
158 /// passing the path of the file you're trying to open. This will give you a
159 /// [`io::Result`][result] with a [`File`][file] inside that you can further
162 /// [`new`]: struct.OpenOptions.html#method.new
163 /// [`open`]: struct.OpenOptions.html#method.open
164 /// [result]: ../io/type.Result.html
165 /// [file]: struct.File.html
169 /// Opening a file to read:
172 /// use std::fs::OpenOptions;
174 /// let file = OpenOptions::new().read(true).open("foo.txt");
177 /// Opening a file for both reading and writing, as well as creating it if it
181 /// use std::fs::OpenOptions;
183 /// let file = OpenOptions::new()
187 /// .open("foo.txt");
189 #[derive(Clone, Debug)]
190 #[stable(feature = "rust1", since = "1.0.0")]
191 pub struct OpenOptions(fs_imp::OpenOptions);
193 /// Representation of the various permissions on a file.
195 /// This module only currently provides one bit of information, [`readonly`],
196 /// which is exposed on all currently supported platforms. Unix-specific
197 /// functionality, such as mode bits, is available through the
198 /// [`PermissionsExt`] trait.
200 /// [`readonly`]: struct.Permissions.html#method.readonly
201 /// [`PermissionsExt`]: ../os/unix/fs/trait.PermissionsExt.html
202 #[derive(Clone, PartialEq, Eq, Debug)]
203 #[stable(feature = "rust1", since = "1.0.0")]
204 pub struct Permissions(fs_imp::FilePermissions);
206 /// A structure representing a type of file with accessors for each file type.
207 /// It is returned by [`Metadata::file_type`] method.
209 /// [`Metadata::file_type`]: struct.Metadata.html#method.file_type
210 #[stable(feature = "file_type", since = "1.1.0")]
211 #[derive(Copy, Clone, PartialEq, Eq, Hash, Debug)]
212 pub struct FileType(fs_imp::FileType);
214 /// A builder used to create directories in various manners.
216 /// This builder also supports platform-specific options.
217 #[stable(feature = "dir_builder", since = "1.6.0")]
219 pub struct DirBuilder {
220 inner: fs_imp::DirBuilder,
224 /// Indicates how large a buffer to pre-allocate before reading the entire file.
225 fn initial_buffer_size(file: &File) -> usize {
226 // Allocate one extra byte so the buffer doesn't need to grow before the
227 // final `read` call at the end of the file. Don't worry about `usize`
228 // overflow because reading will fail regardless in that case.
229 file.metadata().map(|m| m.len() as usize + 1).unwrap_or(0)
232 /// Read the entire contents of a file into a bytes vector.
234 /// This is a convenience function for using [`File::open`] and [`read_to_end`]
235 /// with fewer imports and without an intermediate variable. It pre-allocates a
236 /// buffer based on the file size when available, so it is generally faster than
237 /// reading into a vector created with `Vec::new()`.
239 /// [`File::open`]: struct.File.html#method.open
240 /// [`read_to_end`]: ../io/trait.Read.html#method.read_to_end
244 /// This function will return an error if `path` does not already exist.
245 /// Other errors may also be returned according to [`OpenOptions::open`].
247 /// [`OpenOptions::open`]: struct.OpenOptions.html#method.open
249 /// It will also return an error if it encounters while reading an error
250 /// of a kind other than [`ErrorKind::Interrupted`].
252 /// [`ErrorKind::Interrupted`]: ../../std/io/enum.ErrorKind.html#variant.Interrupted
258 /// use std::net::SocketAddr;
260 /// fn main() -> Result<(), Box<dyn std::error::Error + 'static>> {
261 /// let foo: SocketAddr = String::from_utf8_lossy(&fs::read("address.txt")?).parse()?;
265 #[stable(feature = "fs_read_write_bytes", since = "1.26.0")]
266 pub fn read<P: AsRef<Path>>(path: P) -> io::Result<Vec<u8>> {
267 fn inner(path: &Path) -> io::Result<Vec<u8>> {
268 let mut file = File::open(path)?;
269 let mut bytes = Vec::with_capacity(initial_buffer_size(&file));
270 file.read_to_end(&mut bytes)?;
276 /// Read the entire contents of a file into a string.
278 /// This is a convenience function for using [`File::open`] and [`read_to_string`]
279 /// with fewer imports and without an intermediate variable. It pre-allocates a
280 /// buffer based on the file size when available, so it is generally faster than
281 /// reading into a string created with `String::new()`.
283 /// [`File::open`]: struct.File.html#method.open
284 /// [`read_to_string`]: ../io/trait.Read.html#method.read_to_string
288 /// This function will return an error if `path` does not already exist.
289 /// Other errors may also be returned according to [`OpenOptions::open`].
291 /// [`OpenOptions::open`]: struct.OpenOptions.html#method.open
293 /// It will also return an error if it encounters while reading an error
294 /// of a kind other than [`ErrorKind::Interrupted`],
295 /// or if the contents of the file are not valid UTF-8.
297 /// [`ErrorKind::Interrupted`]: ../../std/io/enum.ErrorKind.html#variant.Interrupted
303 /// use std::net::SocketAddr;
305 /// fn main() -> Result<(), Box<dyn std::error::Error + 'static>> {
306 /// let foo: SocketAddr = fs::read_to_string("address.txt")?.parse()?;
310 #[stable(feature = "fs_read_write", since = "1.26.0")]
311 pub fn read_to_string<P: AsRef<Path>>(path: P) -> io::Result<String> {
312 fn inner(path: &Path) -> io::Result<String> {
313 let mut file = File::open(path)?;
314 let mut string = String::with_capacity(initial_buffer_size(&file));
315 file.read_to_string(&mut string)?;
321 /// Write a slice as the entire contents of a file.
323 /// This function will create a file if it does not exist,
324 /// and will entirely replace its contents if it does.
326 /// This is a convenience function for using [`File::create`] and [`write_all`]
327 /// with fewer imports.
329 /// [`File::create`]: struct.File.html#method.create
330 /// [`write_all`]: ../io/trait.Write.html#method.write_all
337 /// fn main() -> std::io::Result<()> {
338 /// fs::write("foo.txt", b"Lorem ipsum")?;
339 /// fs::write("bar.txt", "dolor sit")?;
343 #[stable(feature = "fs_read_write_bytes", since = "1.26.0")]
344 pub fn write<P: AsRef<Path>, C: AsRef<[u8]>>(path: P, contents: C) -> io::Result<()> {
345 fn inner(path: &Path, contents: &[u8]) -> io::Result<()> {
346 File::create(path)?.write_all(contents)
348 inner(path.as_ref(), contents.as_ref())
352 /// Attempts to open a file in read-only mode.
354 /// See the [`OpenOptions::open`] method for more details.
358 /// This function will return an error if `path` does not already exist.
359 /// Other errors may also be returned according to [`OpenOptions::open`].
361 /// [`OpenOptions::open`]: struct.OpenOptions.html#method.open
366 /// use std::fs::File;
368 /// fn main() -> std::io::Result<()> {
369 /// let mut f = File::open("foo.txt")?;
373 #[stable(feature = "rust1", since = "1.0.0")]
374 pub fn open<P: AsRef<Path>>(path: P) -> io::Result<File> {
375 OpenOptions::new().read(true).open(path.as_ref())
378 /// Opens a file in write-only mode.
380 /// This function will create a file if it does not exist,
381 /// and will truncate it if it does.
383 /// See the [`OpenOptions::open`] function for more details.
385 /// [`OpenOptions::open`]: struct.OpenOptions.html#method.open
390 /// use std::fs::File;
392 /// fn main() -> std::io::Result<()> {
393 /// let mut f = File::create("foo.txt")?;
397 #[stable(feature = "rust1", since = "1.0.0")]
398 pub fn create<P: AsRef<Path>>(path: P) -> io::Result<File> {
399 OpenOptions::new().write(true).create(true).truncate(true).open(path.as_ref())
402 /// Returns a new OpenOptions object.
404 /// This function returns a new OpenOptions object that you can use to
405 /// open or create a file with specific options if `open()` or `create()`
406 /// are not appropriate.
408 /// It is equivalent to `OpenOptions::new()` but allows you to write more
409 /// readable code. Instead of `OpenOptions::new().read(true).open("foo.txt")`
410 /// you can write `File::with_options().read(true).open("foo.txt"). This
411 /// also avoids the need to import `OpenOptions`.
413 /// See the [`OpenOptions::new`] function for more details.
415 /// [`OpenOptions::new`]: struct.OpenOptions.html#method.new
420 /// #![feature(with_options)]
421 /// use std::fs::File;
423 /// fn main() -> std::io::Result<()> {
424 /// let mut f = File::with_options().read(true).open("foo.txt")?;
428 #[unstable(feature = "with_options", issue = "65439")]
429 pub fn with_options() -> OpenOptions {
433 /// Attempts to sync all OS-internal metadata to disk.
435 /// This function will attempt to ensure that all in-memory data reaches the
436 /// filesystem before returning.
438 /// This can be used to handle errors that would otherwise only be caught
439 /// when the `File` is closed. Dropping a file will ignore errors in
440 /// synchronizing this in-memory data.
445 /// use std::fs::File;
446 /// use std::io::prelude::*;
448 /// fn main() -> std::io::Result<()> {
449 /// let mut f = File::create("foo.txt")?;
450 /// f.write_all(b"Hello, world!")?;
456 #[stable(feature = "rust1", since = "1.0.0")]
457 pub fn sync_all(&self) -> io::Result<()> {
461 /// This function is similar to [`sync_all`], except that it may not
462 /// synchronize file metadata to the filesystem.
464 /// This is intended for use cases that must synchronize content, but don't
465 /// need the metadata on disk. The goal of this method is to reduce disk
468 /// Note that some platforms may simply implement this in terms of
471 /// [`sync_all`]: struct.File.html#method.sync_all
476 /// use std::fs::File;
477 /// use std::io::prelude::*;
479 /// fn main() -> std::io::Result<()> {
480 /// let mut f = File::create("foo.txt")?;
481 /// f.write_all(b"Hello, world!")?;
487 #[stable(feature = "rust1", since = "1.0.0")]
488 pub fn sync_data(&self) -> io::Result<()> {
489 self.inner.datasync()
492 /// Truncates or extends the underlying file, updating the size of
493 /// this file to become `size`.
495 /// If the `size` is less than the current file's size, then the file will
496 /// be shrunk. If it is greater than the current file's size, then the file
497 /// will be extended to `size` and have all of the intermediate data filled
500 /// The file's cursor isn't changed. In particular, if the cursor was at the
501 /// end and the file is shrunk using this operation, the cursor will now be
506 /// This function will return an error if the file is not opened for writing.
507 /// Also, std::io::ErrorKind::InvalidInput will be returned if the desired
508 /// length would cause an overflow due to the implementation specifics.
513 /// use std::fs::File;
515 /// fn main() -> std::io::Result<()> {
516 /// let mut f = File::create("foo.txt")?;
522 /// Note that this method alters the content of the underlying file, even
523 /// though it takes `&self` rather than `&mut self`.
524 #[stable(feature = "rust1", since = "1.0.0")]
525 pub fn set_len(&self, size: u64) -> io::Result<()> {
526 self.inner.truncate(size)
529 /// Queries metadata about the underlying file.
534 /// use std::fs::File;
536 /// fn main() -> std::io::Result<()> {
537 /// let mut f = File::open("foo.txt")?;
538 /// let metadata = f.metadata()?;
542 #[stable(feature = "rust1", since = "1.0.0")]
543 pub fn metadata(&self) -> io::Result<Metadata> {
544 self.inner.file_attr().map(Metadata)
547 /// Creates a new `File` instance that shares the same underlying file handle
548 /// as the existing `File` instance. Reads, writes, and seeks will affect
549 /// both `File` instances simultaneously.
553 /// Creates two handles for a file named `foo.txt`:
556 /// use std::fs::File;
558 /// fn main() -> std::io::Result<()> {
559 /// let mut file = File::open("foo.txt")?;
560 /// let file_copy = file.try_clone()?;
565 /// Assuming there’s a file named `foo.txt` with contents `abcdef\n`, create
566 /// two handles, seek one of them, and read the remaining bytes from the
570 /// use std::fs::File;
571 /// use std::io::SeekFrom;
572 /// use std::io::prelude::*;
574 /// fn main() -> std::io::Result<()> {
575 /// let mut file = File::open("foo.txt")?;
576 /// let mut file_copy = file.try_clone()?;
578 /// file.seek(SeekFrom::Start(3))?;
580 /// let mut contents = vec![];
581 /// file_copy.read_to_end(&mut contents)?;
582 /// assert_eq!(contents, b"def\n");
586 #[stable(feature = "file_try_clone", since = "1.9.0")]
587 pub fn try_clone(&self) -> io::Result<File> {
588 Ok(File { inner: self.inner.duplicate()? })
591 /// Changes the permissions on the underlying file.
593 /// # Platform-specific behavior
595 /// This function currently corresponds to the `fchmod` function on Unix and
596 /// the `SetFileInformationByHandle` function on Windows. Note that, this
597 /// [may change in the future][changes].
599 /// [changes]: ../io/index.html#platform-specific-behavior
603 /// This function will return an error if the user lacks permission change
604 /// attributes on the underlying file. It may also return an error in other
605 /// os-specific unspecified cases.
610 /// fn main() -> std::io::Result<()> {
611 /// use std::fs::File;
613 /// let file = File::open("foo.txt")?;
614 /// let mut perms = file.metadata()?.permissions();
615 /// perms.set_readonly(true);
616 /// file.set_permissions(perms)?;
621 /// Note that this method alters the permissions of the underlying file,
622 /// even though it takes `&self` rather than `&mut self`.
623 #[stable(feature = "set_permissions_atomic", since = "1.16.0")]
624 pub fn set_permissions(&self, perm: Permissions) -> io::Result<()> {
625 self.inner.set_permissions(perm.0)
629 impl AsInner<fs_imp::File> for File {
630 fn as_inner(&self) -> &fs_imp::File {
634 impl FromInner<fs_imp::File> for File {
635 fn from_inner(f: fs_imp::File) -> File {
639 impl IntoInner<fs_imp::File> for File {
640 fn into_inner(self) -> fs_imp::File {
645 #[stable(feature = "rust1", since = "1.0.0")]
646 impl fmt::Debug for File {
647 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
652 #[stable(feature = "rust1", since = "1.0.0")]
654 fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
658 fn read_vectored(&mut self, bufs: &mut [IoSliceMut<'_>]) -> io::Result<usize> {
659 self.inner.read_vectored(bufs)
663 unsafe fn initializer(&self) -> Initializer {
667 #[stable(feature = "rust1", since = "1.0.0")]
668 impl Write for File {
669 fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
670 self.inner.write(buf)
673 fn write_vectored(&mut self, bufs: &[IoSlice<'_>]) -> io::Result<usize> {
674 self.inner.write_vectored(bufs)
677 fn flush(&mut self) -> io::Result<()> {
681 #[stable(feature = "rust1", since = "1.0.0")]
683 fn seek(&mut self, pos: SeekFrom) -> io::Result<u64> {
687 #[stable(feature = "rust1", since = "1.0.0")]
688 impl Read for &File {
689 fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
693 fn read_vectored(&mut self, bufs: &mut [IoSliceMut<'_>]) -> io::Result<usize> {
694 self.inner.read_vectored(bufs)
698 unsafe fn initializer(&self) -> Initializer {
702 #[stable(feature = "rust1", since = "1.0.0")]
703 impl Write for &File {
704 fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
705 self.inner.write(buf)
708 fn write_vectored(&mut self, bufs: &[IoSlice<'_>]) -> io::Result<usize> {
709 self.inner.write_vectored(bufs)
712 fn flush(&mut self) -> io::Result<()> {
716 #[stable(feature = "rust1", since = "1.0.0")]
717 impl Seek for &File {
718 fn seek(&mut self, pos: SeekFrom) -> io::Result<u64> {
724 /// Creates a blank new set of options ready for configuration.
726 /// All options are initially set to `false`.
731 /// use std::fs::OpenOptions;
733 /// let mut options = OpenOptions::new();
734 /// let file = options.read(true).open("foo.txt");
736 #[stable(feature = "rust1", since = "1.0.0")]
737 pub fn new() -> OpenOptions {
738 OpenOptions(fs_imp::OpenOptions::new())
741 /// Sets the option for read access.
743 /// This option, when true, will indicate that the file should be
744 /// `read`-able if opened.
749 /// use std::fs::OpenOptions;
751 /// let file = OpenOptions::new().read(true).open("foo.txt");
753 #[stable(feature = "rust1", since = "1.0.0")]
754 pub fn read(&mut self, read: bool) -> &mut OpenOptions {
759 /// Sets the option for write access.
761 /// This option, when true, will indicate that the file should be
762 /// `write`-able if opened.
764 /// If the file already exists, any write calls on it will overwrite its
765 /// contents, without truncating it.
770 /// use std::fs::OpenOptions;
772 /// let file = OpenOptions::new().write(true).open("foo.txt");
774 #[stable(feature = "rust1", since = "1.0.0")]
775 pub fn write(&mut self, write: bool) -> &mut OpenOptions {
780 /// Sets the option for the append mode.
782 /// This option, when true, means that writes will append to a file instead
783 /// of overwriting previous contents.
784 /// Note that setting `.write(true).append(true)` has the same effect as
785 /// setting only `.append(true)`.
787 /// For most filesystems, the operating system guarantees that all writes are
788 /// atomic: no writes get mangled because another process writes at the same
791 /// One maybe obvious note when using append-mode: make sure that all data
792 /// that belongs together is written to the file in one operation. This
793 /// can be done by concatenating strings before passing them to [`write()`],
794 /// or using a buffered writer (with a buffer of adequate size),
795 /// and calling [`flush()`] when the message is complete.
797 /// If a file is opened with both read and append access, beware that after
798 /// opening, and after every write, the position for reading may be set at the
799 /// end of the file. So, before writing, save the current position (using
800 /// [`seek`]`(`[`SeekFrom`]`::`[`Current`]`(0))`), and restore it before the next read.
804 /// This function doesn't create the file if it doesn't exist. Use the [`create`]
807 /// [`write()`]: ../../std/fs/struct.File.html#method.write
808 /// [`flush()`]: ../../std/fs/struct.File.html#method.flush
809 /// [`seek`]: ../../std/fs/struct.File.html#method.seek
810 /// [`SeekFrom`]: ../../std/io/enum.SeekFrom.html
811 /// [`Current`]: ../../std/io/enum.SeekFrom.html#variant.Current
812 /// [`create`]: #method.create
817 /// use std::fs::OpenOptions;
819 /// let file = OpenOptions::new().append(true).open("foo.txt");
821 #[stable(feature = "rust1", since = "1.0.0")]
822 pub fn append(&mut self, append: bool) -> &mut OpenOptions {
823 self.0.append(append);
827 /// Sets the option for truncating a previous file.
829 /// If a file is successfully opened with this option set it will truncate
830 /// the file to 0 length if it already exists.
832 /// The file must be opened with write access for truncate to work.
837 /// use std::fs::OpenOptions;
839 /// let file = OpenOptions::new().write(true).truncate(true).open("foo.txt");
841 #[stable(feature = "rust1", since = "1.0.0")]
842 pub fn truncate(&mut self, truncate: bool) -> &mut OpenOptions {
843 self.0.truncate(truncate);
847 /// Sets the option for creating a new file.
849 /// This option indicates whether a new file will be created if the file
850 /// does not yet already exist.
852 /// In order for the file to be created, [`write`] or [`append`] access must
855 /// [`write`]: #method.write
856 /// [`append`]: #method.append
861 /// use std::fs::OpenOptions;
863 /// let file = OpenOptions::new().write(true).create(true).open("foo.txt");
865 #[stable(feature = "rust1", since = "1.0.0")]
866 pub fn create(&mut self, create: bool) -> &mut OpenOptions {
867 self.0.create(create);
871 /// Sets the option to always create a new file.
873 /// This option indicates whether a new file will be created.
874 /// No file is allowed to exist at the target location, also no (dangling)
877 /// This option is useful because it is atomic. Otherwise between checking
878 /// whether a file exists and creating a new one, the file may have been
879 /// created by another process (a TOCTOU race condition / attack).
881 /// If `.create_new(true)` is set, [`.create()`] and [`.truncate()`] are
884 /// The file must be opened with write or append access in order to create
887 /// [`.create()`]: #method.create
888 /// [`.truncate()`]: #method.truncate
893 /// use std::fs::OpenOptions;
895 /// let file = OpenOptions::new().write(true)
896 /// .create_new(true)
897 /// .open("foo.txt");
899 #[stable(feature = "expand_open_options2", since = "1.9.0")]
900 pub fn create_new(&mut self, create_new: bool) -> &mut OpenOptions {
901 self.0.create_new(create_new);
905 /// Opens a file at `path` with the options specified by `self`.
909 /// This function will return an error under a number of different
910 /// circumstances. Some of these error conditions are listed here, together
911 /// with their [`ErrorKind`]. The mapping to [`ErrorKind`]s is not part of
912 /// the compatibility contract of the function, especially the `Other` kind
913 /// might change to more specific kinds in the future.
915 /// * [`NotFound`]: The specified file does not exist and neither `create`
916 /// or `create_new` is set.
917 /// * [`NotFound`]: One of the directory components of the file path does
919 /// * [`PermissionDenied`]: The user lacks permission to get the specified
920 /// access rights for the file.
921 /// * [`PermissionDenied`]: The user lacks permission to open one of the
922 /// directory components of the specified path.
923 /// * [`AlreadyExists`]: `create_new` was specified and the file already
925 /// * [`InvalidInput`]: Invalid combinations of open options (truncate
926 /// without write access, no access mode set, etc.).
927 /// * [`Other`]: One of the directory components of the specified file path
928 /// was not, in fact, a directory.
929 /// * [`Other`]: Filesystem-level errors: full disk, write permission
930 /// requested on a read-only file system, exceeded disk quota, too many
931 /// open files, too long filename, too many symbolic links in the
932 /// specified path (Unix-like systems only), etc.
937 /// use std::fs::OpenOptions;
939 /// let file = OpenOptions::new().read(true).open("foo.txt");
942 /// [`ErrorKind`]: ../io/enum.ErrorKind.html
943 /// [`AlreadyExists`]: ../io/enum.ErrorKind.html#variant.AlreadyExists
944 /// [`InvalidInput`]: ../io/enum.ErrorKind.html#variant.InvalidInput
945 /// [`NotFound`]: ../io/enum.ErrorKind.html#variant.NotFound
946 /// [`Other`]: ../io/enum.ErrorKind.html#variant.Other
947 /// [`PermissionDenied`]: ../io/enum.ErrorKind.html#variant.PermissionDenied
948 #[stable(feature = "rust1", since = "1.0.0")]
949 pub fn open<P: AsRef<Path>>(&self, path: P) -> io::Result<File> {
950 self._open(path.as_ref())
953 fn _open(&self, path: &Path) -> io::Result<File> {
954 fs_imp::File::open(path, &self.0).map(|inner| File { inner })
958 impl AsInner<fs_imp::OpenOptions> for OpenOptions {
959 fn as_inner(&self) -> &fs_imp::OpenOptions {
964 impl AsInnerMut<fs_imp::OpenOptions> for OpenOptions {
965 fn as_inner_mut(&mut self) -> &mut fs_imp::OpenOptions {
971 /// Returns the file type for this metadata.
976 /// fn main() -> std::io::Result<()> {
979 /// let metadata = fs::metadata("foo.txt")?;
981 /// println!("{:?}", metadata.file_type());
985 #[stable(feature = "file_type", since = "1.1.0")]
986 pub fn file_type(&self) -> FileType {
987 FileType(self.0.file_type())
990 /// Returns `true` if this metadata is for a directory. The
991 /// result is mutually exclusive to the result of
992 /// [`is_file`], and will be false for symlink metadata
993 /// obtained from [`symlink_metadata`].
995 /// [`is_file`]: struct.Metadata.html#method.is_file
996 /// [`symlink_metadata`]: fn.symlink_metadata.html
1001 /// fn main() -> std::io::Result<()> {
1004 /// let metadata = fs::metadata("foo.txt")?;
1006 /// assert!(!metadata.is_dir());
1010 #[stable(feature = "rust1", since = "1.0.0")]
1011 pub fn is_dir(&self) -> bool {
1012 self.file_type().is_dir()
1015 /// Returns `true` if this metadata is for a regular file. The
1016 /// result is mutually exclusive to the result of
1017 /// [`is_dir`], and will be false for symlink metadata
1018 /// obtained from [`symlink_metadata`].
1020 /// [`is_dir`]: struct.Metadata.html#method.is_dir
1021 /// [`symlink_metadata`]: fn.symlink_metadata.html
1028 /// fn main() -> std::io::Result<()> {
1029 /// let metadata = fs::metadata("foo.txt")?;
1031 /// assert!(metadata.is_file());
1035 #[stable(feature = "rust1", since = "1.0.0")]
1036 pub fn is_file(&self) -> bool {
1037 self.file_type().is_file()
1040 /// Returns the size of the file, in bytes, this metadata is for.
1047 /// fn main() -> std::io::Result<()> {
1048 /// let metadata = fs::metadata("foo.txt")?;
1050 /// assert_eq!(0, metadata.len());
1054 #[stable(feature = "rust1", since = "1.0.0")]
1055 pub fn len(&self) -> u64 {
1059 /// Returns the permissions of the file this metadata is for.
1066 /// fn main() -> std::io::Result<()> {
1067 /// let metadata = fs::metadata("foo.txt")?;
1069 /// assert!(!metadata.permissions().readonly());
1073 #[stable(feature = "rust1", since = "1.0.0")]
1074 pub fn permissions(&self) -> Permissions {
1075 Permissions(self.0.perm())
1078 /// Returns the last modification time listed in this metadata.
1080 /// The returned value corresponds to the `mtime` field of `stat` on Unix
1081 /// platforms and the `ftLastWriteTime` field on Windows platforms.
1085 /// This field may not be available on all platforms, and will return an
1086 /// `Err` on platforms where it is not available.
1093 /// fn main() -> std::io::Result<()> {
1094 /// let metadata = fs::metadata("foo.txt")?;
1096 /// if let Ok(time) = metadata.modified() {
1097 /// println!("{:?}", time);
1099 /// println!("Not supported on this platform");
1104 #[stable(feature = "fs_time", since = "1.10.0")]
1105 pub fn modified(&self) -> io::Result<SystemTime> {
1106 self.0.modified().map(FromInner::from_inner)
1109 /// Returns the last access time of this metadata.
1111 /// The returned value corresponds to the `atime` field of `stat` on Unix
1112 /// platforms and the `ftLastAccessTime` field on Windows platforms.
1114 /// Note that not all platforms will keep this field update in a file's
1115 /// metadata, for example Windows has an option to disable updating this
1116 /// time when files are accessed and Linux similarly has `noatime`.
1120 /// This field may not be available on all platforms, and will return an
1121 /// `Err` on platforms where it is not available.
1128 /// fn main() -> std::io::Result<()> {
1129 /// let metadata = fs::metadata("foo.txt")?;
1131 /// if let Ok(time) = metadata.accessed() {
1132 /// println!("{:?}", time);
1134 /// println!("Not supported on this platform");
1139 #[stable(feature = "fs_time", since = "1.10.0")]
1140 pub fn accessed(&self) -> io::Result<SystemTime> {
1141 self.0.accessed().map(FromInner::from_inner)
1144 /// Returns the creation time listed in this metadata.
1146 /// The returned value corresponds to the `btime` field of `statx` on
1147 /// Linux kernel starting from to 4.11, the `birthtime` field of `stat` on other
1148 /// Unix platforms, and the `ftCreationTime` field on Windows platforms.
1152 /// This field may not be available on all platforms, and will return an
1153 /// `Err` on platforms or filesystems where it is not available.
1160 /// fn main() -> std::io::Result<()> {
1161 /// let metadata = fs::metadata("foo.txt")?;
1163 /// if let Ok(time) = metadata.created() {
1164 /// println!("{:?}", time);
1166 /// println!("Not supported on this platform or filesystem");
1171 #[stable(feature = "fs_time", since = "1.10.0")]
1172 pub fn created(&self) -> io::Result<SystemTime> {
1173 self.0.created().map(FromInner::from_inner)
1177 #[stable(feature = "std_debug", since = "1.16.0")]
1178 impl fmt::Debug for Metadata {
1179 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1180 f.debug_struct("Metadata")
1181 .field("file_type", &self.file_type())
1182 .field("is_dir", &self.is_dir())
1183 .field("is_file", &self.is_file())
1184 .field("permissions", &self.permissions())
1185 .field("modified", &self.modified())
1186 .field("accessed", &self.accessed())
1187 .field("created", &self.created())
1192 impl AsInner<fs_imp::FileAttr> for Metadata {
1193 fn as_inner(&self) -> &fs_imp::FileAttr {
1198 impl FromInner<fs_imp::FileAttr> for Metadata {
1199 fn from_inner(attr: fs_imp::FileAttr) -> Metadata {
1205 /// Returns `true` if these permissions describe a readonly (unwritable) file.
1210 /// use std::fs::File;
1212 /// fn main() -> std::io::Result<()> {
1213 /// let mut f = File::create("foo.txt")?;
1214 /// let metadata = f.metadata()?;
1216 /// assert_eq!(false, metadata.permissions().readonly());
1220 #[stable(feature = "rust1", since = "1.0.0")]
1221 pub fn readonly(&self) -> bool {
1225 /// Modifies the readonly flag for this set of permissions. If the
1226 /// `readonly` argument is `true`, using the resulting `Permission` will
1227 /// update file permissions to forbid writing. Conversely, if it's `false`,
1228 /// using the resulting `Permission` will update file permissions to allow
1231 /// This operation does **not** modify the filesystem. To modify the
1232 /// filesystem use the [`fs::set_permissions`] function.
1234 /// [`fs::set_permissions`]: fn.set_permissions.html
1239 /// use std::fs::File;
1241 /// fn main() -> std::io::Result<()> {
1242 /// let f = File::create("foo.txt")?;
1243 /// let metadata = f.metadata()?;
1244 /// let mut permissions = metadata.permissions();
1246 /// permissions.set_readonly(true);
1248 /// // filesystem doesn't change
1249 /// assert_eq!(false, metadata.permissions().readonly());
1251 /// // just this particular `permissions`.
1252 /// assert_eq!(true, permissions.readonly());
1256 #[stable(feature = "rust1", since = "1.0.0")]
1257 pub fn set_readonly(&mut self, readonly: bool) {
1258 self.0.set_readonly(readonly)
1263 /// Tests whether this file type represents a directory. The
1264 /// result is mutually exclusive to the results of
1265 /// [`is_file`] and [`is_symlink`]; only zero or one of these
1268 /// [`is_file`]: struct.FileType.html#method.is_file
1269 /// [`is_symlink`]: struct.FileType.html#method.is_symlink
1274 /// fn main() -> std::io::Result<()> {
1277 /// let metadata = fs::metadata("foo.txt")?;
1278 /// let file_type = metadata.file_type();
1280 /// assert_eq!(file_type.is_dir(), false);
1284 #[stable(feature = "file_type", since = "1.1.0")]
1285 pub fn is_dir(&self) -> bool {
1289 /// Tests whether this file type represents a regular file.
1290 /// The result is mutually exclusive to the results of
1291 /// [`is_dir`] and [`is_symlink`]; only zero or one of these
1294 /// [`is_dir`]: struct.FileType.html#method.is_dir
1295 /// [`is_symlink`]: struct.FileType.html#method.is_symlink
1300 /// fn main() -> std::io::Result<()> {
1303 /// let metadata = fs::metadata("foo.txt")?;
1304 /// let file_type = metadata.file_type();
1306 /// assert_eq!(file_type.is_file(), true);
1310 #[stable(feature = "file_type", since = "1.1.0")]
1311 pub fn is_file(&self) -> bool {
1315 /// Tests whether this file type represents a symbolic link.
1316 /// The result is mutually exclusive to the results of
1317 /// [`is_dir`] and [`is_file`]; only zero or one of these
1320 /// The underlying [`Metadata`] struct needs to be retrieved
1321 /// with the [`fs::symlink_metadata`] function and not the
1322 /// [`fs::metadata`] function. The [`fs::metadata`] function
1323 /// follows symbolic links, so [`is_symlink`] would always
1324 /// return `false` for the target file.
1326 /// [`Metadata`]: struct.Metadata.html
1327 /// [`fs::metadata`]: fn.metadata.html
1328 /// [`fs::symlink_metadata`]: fn.symlink_metadata.html
1329 /// [`is_dir`]: struct.FileType.html#method.is_dir
1330 /// [`is_file`]: struct.FileType.html#method.is_file
1331 /// [`is_symlink`]: struct.FileType.html#method.is_symlink
1338 /// fn main() -> std::io::Result<()> {
1339 /// let metadata = fs::symlink_metadata("foo.txt")?;
1340 /// let file_type = metadata.file_type();
1342 /// assert_eq!(file_type.is_symlink(), false);
1346 #[stable(feature = "file_type", since = "1.1.0")]
1347 pub fn is_symlink(&self) -> bool {
1352 impl AsInner<fs_imp::FileType> for FileType {
1353 fn as_inner(&self) -> &fs_imp::FileType {
1358 impl FromInner<fs_imp::FilePermissions> for Permissions {
1359 fn from_inner(f: fs_imp::FilePermissions) -> Permissions {
1364 impl AsInner<fs_imp::FilePermissions> for Permissions {
1365 fn as_inner(&self) -> &fs_imp::FilePermissions {
1370 #[stable(feature = "rust1", since = "1.0.0")]
1371 impl Iterator for ReadDir {
1372 type Item = io::Result<DirEntry>;
1374 fn next(&mut self) -> Option<io::Result<DirEntry>> {
1375 self.0.next().map(|entry| entry.map(DirEntry))
1380 /// Returns the full path to the file that this entry represents.
1382 /// The full path is created by joining the original path to `read_dir`
1383 /// with the filename of this entry.
1390 /// fn main() -> std::io::Result<()> {
1391 /// for entry in fs::read_dir(".")? {
1392 /// let dir = entry?;
1393 /// println!("{:?}", dir.path());
1399 /// This prints output like:
1402 /// "./whatever.txt"
1404 /// "./hello_world.rs"
1407 /// The exact text, of course, depends on what files you have in `.`.
1408 #[stable(feature = "rust1", since = "1.0.0")]
1409 pub fn path(&self) -> PathBuf {
1413 /// Returns the metadata for the file that this entry points at.
1415 /// This function will not traverse symlinks if this entry points at a
1418 /// # Platform-specific behavior
1420 /// On Windows this function is cheap to call (no extra system calls
1421 /// needed), but on Unix platforms this function is the equivalent of
1422 /// calling `symlink_metadata` on the path.
1429 /// if let Ok(entries) = fs::read_dir(".") {
1430 /// for entry in entries {
1431 /// if let Ok(entry) = entry {
1432 /// // Here, `entry` is a `DirEntry`.
1433 /// if let Ok(metadata) = entry.metadata() {
1434 /// // Now let's show our entry's permissions!
1435 /// println!("{:?}: {:?}", entry.path(), metadata.permissions());
1437 /// println!("Couldn't get metadata for {:?}", entry.path());
1443 #[stable(feature = "dir_entry_ext", since = "1.1.0")]
1444 pub fn metadata(&self) -> io::Result<Metadata> {
1445 self.0.metadata().map(Metadata)
1448 /// Returns the file type for the file that this entry points at.
1450 /// This function will not traverse symlinks if this entry points at a
1453 /// # Platform-specific behavior
1455 /// On Windows and most Unix platforms this function is free (no extra
1456 /// system calls needed), but some Unix platforms may require the equivalent
1457 /// call to `symlink_metadata` to learn about the target file type.
1464 /// if let Ok(entries) = fs::read_dir(".") {
1465 /// for entry in entries {
1466 /// if let Ok(entry) = entry {
1467 /// // Here, `entry` is a `DirEntry`.
1468 /// if let Ok(file_type) = entry.file_type() {
1469 /// // Now let's show our entry's file type!
1470 /// println!("{:?}: {:?}", entry.path(), file_type);
1472 /// println!("Couldn't get file type for {:?}", entry.path());
1478 #[stable(feature = "dir_entry_ext", since = "1.1.0")]
1479 pub fn file_type(&self) -> io::Result<FileType> {
1480 self.0.file_type().map(FileType)
1483 /// Returns the bare file name of this directory entry without any other
1484 /// leading path component.
1491 /// if let Ok(entries) = fs::read_dir(".") {
1492 /// for entry in entries {
1493 /// if let Ok(entry) = entry {
1494 /// // Here, `entry` is a `DirEntry`.
1495 /// println!("{:?}", entry.file_name());
1500 #[stable(feature = "dir_entry_ext", since = "1.1.0")]
1501 pub fn file_name(&self) -> OsString {
1506 #[stable(feature = "dir_entry_debug", since = "1.13.0")]
1507 impl fmt::Debug for DirEntry {
1508 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1509 f.debug_tuple("DirEntry").field(&self.path()).finish()
1513 impl AsInner<fs_imp::DirEntry> for DirEntry {
1514 fn as_inner(&self) -> &fs_imp::DirEntry {
1519 /// Removes a file from the filesystem.
1521 /// Note that there is no
1522 /// guarantee that the file is immediately deleted (e.g., depending on
1523 /// platform, other open file descriptors may prevent immediate removal).
1525 /// # Platform-specific behavior
1527 /// This function currently corresponds to the `unlink` function on Unix
1528 /// and the `DeleteFile` function on Windows.
1529 /// Note that, this [may change in the future][changes].
1531 /// [changes]: ../io/index.html#platform-specific-behavior
1535 /// This function will return an error in the following situations, but is not
1536 /// limited to just these cases:
1538 /// * `path` points to a directory.
1539 /// * The user lacks permissions to remove the file.
1546 /// fn main() -> std::io::Result<()> {
1547 /// fs::remove_file("a.txt")?;
1551 #[stable(feature = "rust1", since = "1.0.0")]
1552 pub fn remove_file<P: AsRef<Path>>(path: P) -> io::Result<()> {
1553 fs_imp::unlink(path.as_ref())
1556 /// Given a path, query the file system to get information about a file,
1559 /// This function will traverse symbolic links to query information about the
1560 /// destination file.
1562 /// # Platform-specific behavior
1564 /// This function currently corresponds to the `stat` function on Unix
1565 /// and the `GetFileAttributesEx` function on Windows.
1566 /// Note that, this [may change in the future][changes].
1568 /// [changes]: ../io/index.html#platform-specific-behavior
1572 /// This function will return an error in the following situations, but is not
1573 /// limited to just these cases:
1575 /// * The user lacks permissions to perform `metadata` call on `path`.
1576 /// * `path` does not exist.
1583 /// fn main() -> std::io::Result<()> {
1584 /// let attr = fs::metadata("/some/file/path.txt")?;
1585 /// // inspect attr ...
1589 #[stable(feature = "rust1", since = "1.0.0")]
1590 pub fn metadata<P: AsRef<Path>>(path: P) -> io::Result<Metadata> {
1591 fs_imp::stat(path.as_ref()).map(Metadata)
1594 /// Query the metadata about a file without following symlinks.
1596 /// # Platform-specific behavior
1598 /// This function currently corresponds to the `lstat` function on Unix
1599 /// and the `GetFileAttributesEx` function on Windows.
1600 /// Note that, this [may change in the future][changes].
1602 /// [changes]: ../io/index.html#platform-specific-behavior
1606 /// This function will return an error in the following situations, but is not
1607 /// limited to just these cases:
1609 /// * The user lacks permissions to perform `metadata` call on `path`.
1610 /// * `path` does not exist.
1617 /// fn main() -> std::io::Result<()> {
1618 /// let attr = fs::symlink_metadata("/some/file/path.txt")?;
1619 /// // inspect attr ...
1623 #[stable(feature = "symlink_metadata", since = "1.1.0")]
1624 pub fn symlink_metadata<P: AsRef<Path>>(path: P) -> io::Result<Metadata> {
1625 fs_imp::lstat(path.as_ref()).map(Metadata)
1628 /// Rename a file or directory to a new name, replacing the original file if
1629 /// `to` already exists.
1631 /// This will not work if the new name is on a different mount point.
1633 /// # Platform-specific behavior
1635 /// This function currently corresponds to the `rename` function on Unix
1636 /// and the `MoveFileEx` function with the `MOVEFILE_REPLACE_EXISTING` flag on Windows.
1638 /// Because of this, the behavior when both `from` and `to` exist differs. On
1639 /// Unix, if `from` is a directory, `to` must also be an (empty) directory. If
1640 /// `from` is not a directory, `to` must also be not a directory. In contrast,
1641 /// on Windows, `from` can be anything, but `to` must *not* be a directory.
1643 /// Note that, this [may change in the future][changes].
1645 /// [changes]: ../io/index.html#platform-specific-behavior
1649 /// This function will return an error in the following situations, but is not
1650 /// limited to just these cases:
1652 /// * `from` does not exist.
1653 /// * The user lacks permissions to view contents.
1654 /// * `from` and `to` are on separate filesystems.
1661 /// fn main() -> std::io::Result<()> {
1662 /// fs::rename("a.txt", "b.txt")?; // Rename a.txt to b.txt
1666 #[stable(feature = "rust1", since = "1.0.0")]
1667 pub fn rename<P: AsRef<Path>, Q: AsRef<Path>>(from: P, to: Q) -> io::Result<()> {
1668 fs_imp::rename(from.as_ref(), to.as_ref())
1671 /// Copies the contents of one file to another. This function will also
1672 /// copy the permission bits of the original file to the destination file.
1674 /// This function will **overwrite** the contents of `to`.
1676 /// Note that if `from` and `to` both point to the same file, then the file
1677 /// will likely get truncated by this operation.
1679 /// On success, the total number of bytes copied is returned and it is equal to
1680 /// the length of the `to` file as reported by `metadata`.
1682 /// If you’re wanting to copy the contents of one file to another and you’re
1683 /// working with [`File`]s, see the [`io::copy`] function.
1685 /// [`io::copy`]: ../io/fn.copy.html
1686 /// [`File`]: ./struct.File.html
1688 /// # Platform-specific behavior
1690 /// This function currently corresponds to the `open` function in Unix
1691 /// with `O_RDONLY` for `from` and `O_WRONLY`, `O_CREAT`, and `O_TRUNC` for `to`.
1692 /// `O_CLOEXEC` is set for returned file descriptors.
1693 /// On Windows, this function currently corresponds to `CopyFileEx`. Alternate
1694 /// NTFS streams are copied but only the size of the main stream is returned by
1695 /// this function. On MacOS, this function corresponds to `fclonefileat` and
1697 /// Note that, this [may change in the future][changes].
1699 /// [changes]: ../io/index.html#platform-specific-behavior
1703 /// This function will return an error in the following situations, but is not
1704 /// limited to just these cases:
1706 /// * The `from` path is not a file.
1707 /// * The `from` file does not exist.
1708 /// * The current process does not have the permission rights to access
1709 /// `from` or write `to`.
1716 /// fn main() -> std::io::Result<()> {
1717 /// fs::copy("foo.txt", "bar.txt")?; // Copy foo.txt to bar.txt
1721 #[stable(feature = "rust1", since = "1.0.0")]
1722 pub fn copy<P: AsRef<Path>, Q: AsRef<Path>>(from: P, to: Q) -> io::Result<u64> {
1723 fs_imp::copy(from.as_ref(), to.as_ref())
1726 /// Creates a new hard link on the filesystem.
1728 /// The `dst` path will be a link pointing to the `src` path. Note that systems
1729 /// often require these two paths to both be located on the same filesystem.
1731 /// # Platform-specific behavior
1733 /// This function currently corresponds to the `link` function on Unix
1734 /// and the `CreateHardLink` function on Windows.
1735 /// Note that, this [may change in the future][changes].
1737 /// [changes]: ../io/index.html#platform-specific-behavior
1741 /// This function will return an error in the following situations, but is not
1742 /// limited to just these cases:
1744 /// * The `src` path is not a file or doesn't exist.
1751 /// fn main() -> std::io::Result<()> {
1752 /// fs::hard_link("a.txt", "b.txt")?; // Hard link a.txt to b.txt
1756 #[stable(feature = "rust1", since = "1.0.0")]
1757 pub fn hard_link<P: AsRef<Path>, Q: AsRef<Path>>(src: P, dst: Q) -> io::Result<()> {
1758 fs_imp::link(src.as_ref(), dst.as_ref())
1761 /// Creates a new symbolic link on the filesystem.
1763 /// The `dst` path will be a symbolic link pointing to the `src` path.
1764 /// On Windows, this will be a file symlink, not a directory symlink;
1765 /// for this reason, the platform-specific [`std::os::unix::fs::symlink`]
1766 /// and [`std::os::windows::fs::symlink_file`] or [`symlink_dir`] should be
1767 /// used instead to make the intent explicit.
1769 /// [`std::os::unix::fs::symlink`]: ../os/unix/fs/fn.symlink.html
1770 /// [`std::os::windows::fs::symlink_file`]: ../os/windows/fs/fn.symlink_file.html
1771 /// [`symlink_dir`]: ../os/windows/fs/fn.symlink_dir.html
1779 /// fn main() -> std::io::Result<()> {
1780 /// fs::soft_link("a.txt", "b.txt")?;
1784 #[stable(feature = "rust1", since = "1.0.0")]
1787 reason = "replaced with std::os::unix::fs::symlink and \
1788 std::os::windows::fs::{symlink_file, symlink_dir}"
1790 pub fn soft_link<P: AsRef<Path>, Q: AsRef<Path>>(src: P, dst: Q) -> io::Result<()> {
1791 fs_imp::symlink(src.as_ref(), dst.as_ref())
1794 /// Reads a symbolic link, returning the file that the link points to.
1796 /// # Platform-specific behavior
1798 /// This function currently corresponds to the `readlink` function on Unix
1799 /// and the `CreateFile` function with `FILE_FLAG_OPEN_REPARSE_POINT` and
1800 /// `FILE_FLAG_BACKUP_SEMANTICS` flags on Windows.
1801 /// Note that, this [may change in the future][changes].
1803 /// [changes]: ../io/index.html#platform-specific-behavior
1807 /// This function will return an error in the following situations, but is not
1808 /// limited to just these cases:
1810 /// * `path` is not a symbolic link.
1811 /// * `path` does not exist.
1818 /// fn main() -> std::io::Result<()> {
1819 /// let path = fs::read_link("a.txt")?;
1823 #[stable(feature = "rust1", since = "1.0.0")]
1824 pub fn read_link<P: AsRef<Path>>(path: P) -> io::Result<PathBuf> {
1825 fs_imp::readlink(path.as_ref())
1828 /// Returns the canonical, absolute form of a path with all intermediate
1829 /// components normalized and symbolic links resolved.
1831 /// # Platform-specific behavior
1833 /// This function currently corresponds to the `realpath` function on Unix
1834 /// and the `CreateFile` and `GetFinalPathNameByHandle` functions on Windows.
1835 /// Note that, this [may change in the future][changes].
1837 /// On Windows, this converts the path to use [extended length path][path]
1838 /// syntax, which allows your program to use longer path names, but means you
1839 /// can only join backslash-delimited paths to it, and it may be incompatible
1840 /// with other applications (if passed to the application on the command-line,
1841 /// or written to a file another application may read).
1843 /// [changes]: ../io/index.html#platform-specific-behavior
1844 /// [path]: https://msdn.microsoft.com/en-us/library/windows/desktop/aa365247(v=vs.85).aspx#maxpath
1848 /// This function will return an error in the following situations, but is not
1849 /// limited to just these cases:
1851 /// * `path` does not exist.
1852 /// * A non-final component in path is not a directory.
1859 /// fn main() -> std::io::Result<()> {
1860 /// let path = fs::canonicalize("../a/../foo.txt")?;
1864 #[stable(feature = "fs_canonicalize", since = "1.5.0")]
1865 pub fn canonicalize<P: AsRef<Path>>(path: P) -> io::Result<PathBuf> {
1866 fs_imp::canonicalize(path.as_ref())
1869 /// Creates a new, empty directory at the provided path
1871 /// # Platform-specific behavior
1873 /// This function currently corresponds to the `mkdir` function on Unix
1874 /// and the `CreateDirectory` function on Windows.
1875 /// Note that, this [may change in the future][changes].
1877 /// [changes]: ../io/index.html#platform-specific-behavior
1879 /// **NOTE**: If a parent of the given path doesn't exist, this function will
1880 /// return an error. To create a directory and all its missing parents at the
1881 /// same time, use the [`create_dir_all`] function.
1885 /// This function will return an error in the following situations, but is not
1886 /// limited to just these cases:
1888 /// * User lacks permissions to create directory at `path`.
1889 /// * A parent of the given path doesn't exist. (To create a directory and all
1890 /// its missing parents at the same time, use the [`create_dir_all`]
1892 /// * `path` already exists.
1894 /// [`create_dir_all`]: fn.create_dir_all.html
1901 /// fn main() -> std::io::Result<()> {
1902 /// fs::create_dir("/some/dir")?;
1906 #[stable(feature = "rust1", since = "1.0.0")]
1907 pub fn create_dir<P: AsRef<Path>>(path: P) -> io::Result<()> {
1908 DirBuilder::new().create(path.as_ref())
1911 /// Recursively create a directory and all of its parent components if they
1914 /// # Platform-specific behavior
1916 /// This function currently corresponds to the `mkdir` function on Unix
1917 /// and the `CreateDirectory` function on Windows.
1918 /// Note that, this [may change in the future][changes].
1920 /// [changes]: ../io/index.html#platform-specific-behavior
1924 /// This function will return an error in the following situations, but is not
1925 /// limited to just these cases:
1927 /// * If any directory in the path specified by `path`
1928 /// does not already exist and it could not be created otherwise. The specific
1929 /// error conditions for when a directory is being created (after it is
1930 /// determined to not exist) are outlined by [`fs::create_dir`].
1932 /// Notable exception is made for situations where any of the directories
1933 /// specified in the `path` could not be created as it was being created concurrently.
1934 /// Such cases are considered to be successful. That is, calling `create_dir_all`
1935 /// concurrently from multiple threads or processes is guaranteed not to fail
1936 /// due to a race condition with itself.
1938 /// [`fs::create_dir`]: fn.create_dir.html
1945 /// fn main() -> std::io::Result<()> {
1946 /// fs::create_dir_all("/some/dir")?;
1950 #[stable(feature = "rust1", since = "1.0.0")]
1951 pub fn create_dir_all<P: AsRef<Path>>(path: P) -> io::Result<()> {
1952 DirBuilder::new().recursive(true).create(path.as_ref())
1955 /// Removes an existing, empty directory.
1957 /// # Platform-specific behavior
1959 /// This function currently corresponds to the `rmdir` function on Unix
1960 /// and the `RemoveDirectory` function on Windows.
1961 /// Note that, this [may change in the future][changes].
1963 /// [changes]: ../io/index.html#platform-specific-behavior
1967 /// This function will return an error in the following situations, but is not
1968 /// limited to just these cases:
1970 /// * The user lacks permissions to remove the directory at the provided `path`.
1971 /// * The directory isn't empty.
1978 /// fn main() -> std::io::Result<()> {
1979 /// fs::remove_dir("/some/dir")?;
1983 #[stable(feature = "rust1", since = "1.0.0")]
1984 pub fn remove_dir<P: AsRef<Path>>(path: P) -> io::Result<()> {
1985 fs_imp::rmdir(path.as_ref())
1988 /// Removes a directory at this path, after removing all its contents. Use
1991 /// This function does **not** follow symbolic links and it will simply remove the
1992 /// symbolic link itself.
1994 /// # Platform-specific behavior
1996 /// This function currently corresponds to `opendir`, `lstat`, `rm` and `rmdir` functions on Unix
1997 /// and the `FindFirstFile`, `GetFileAttributesEx`, `DeleteFile`, and `RemoveDirectory` functions
1999 /// Note that, this [may change in the future][changes].
2001 /// [changes]: ../io/index.html#platform-specific-behavior
2005 /// See [`fs::remove_file`] and [`fs::remove_dir`].
2007 /// [`fs::remove_file`]: fn.remove_file.html
2008 /// [`fs::remove_dir`]: fn.remove_dir.html
2015 /// fn main() -> std::io::Result<()> {
2016 /// fs::remove_dir_all("/some/dir")?;
2020 #[stable(feature = "rust1", since = "1.0.0")]
2021 pub fn remove_dir_all<P: AsRef<Path>>(path: P) -> io::Result<()> {
2022 fs_imp::remove_dir_all(path.as_ref())
2025 /// Returns an iterator over the entries within a directory.
2027 /// The iterator will yield instances of [`io::Result`]`<`[`DirEntry`]`>`.
2028 /// New errors may be encountered after an iterator is initially constructed.
2030 /// [`io::Result`]: ../io/type.Result.html
2031 /// [`DirEntry`]: struct.DirEntry.html
2033 /// # Platform-specific behavior
2035 /// This function currently corresponds to the `opendir` function on Unix
2036 /// and the `FindFirstFile` function on Windows. Advancing the iterator
2037 /// currently corresponds to `readdir` on Unix and `FindNextFile` on Windows.
2038 /// Note that, this [may change in the future][changes].
2040 /// [changes]: ../io/index.html#platform-specific-behavior
2042 /// The order in which this iterator returns entries is platform and filesystem
2047 /// This function will return an error in the following situations, but is not
2048 /// limited to just these cases:
2050 /// * The provided `path` doesn't exist.
2051 /// * The process lacks permissions to view the contents.
2052 /// * The `path` points at a non-directory file.
2058 /// use std::fs::{self, DirEntry};
2059 /// use std::path::Path;
2061 /// // one possible implementation of walking a directory only visiting files
2062 /// fn visit_dirs(dir: &Path, cb: &dyn Fn(&DirEntry)) -> io::Result<()> {
2063 /// if dir.is_dir() {
2064 /// for entry in fs::read_dir(dir)? {
2065 /// let entry = entry?;
2066 /// let path = entry.path();
2067 /// if path.is_dir() {
2068 /// visit_dirs(&path, cb)?;
2079 /// use std::{fs, io};
2081 /// fn main() -> io::Result<()> {
2082 /// let mut entries = fs::read_dir(".")?
2083 /// .map(|res| res.map(|e| e.path()))
2084 /// .collect::<Result<Vec<_>, io::Error>>()?;
2086 /// // The order in which `read_dir` returns entries is not guaranteed. If reproducible
2087 /// // ordering is required the entries should be explicitly sorted.
2091 /// // The entries have now been sorted by their path.
2096 #[stable(feature = "rust1", since = "1.0.0")]
2097 pub fn read_dir<P: AsRef<Path>>(path: P) -> io::Result<ReadDir> {
2098 fs_imp::readdir(path.as_ref()).map(ReadDir)
2101 /// Changes the permissions found on a file or a directory.
2103 /// # Platform-specific behavior
2105 /// This function currently corresponds to the `chmod` function on Unix
2106 /// and the `SetFileAttributes` function on Windows.
2107 /// Note that, this [may change in the future][changes].
2109 /// [changes]: ../io/index.html#platform-specific-behavior
2113 /// This function will return an error in the following situations, but is not
2114 /// limited to just these cases:
2116 /// * `path` does not exist.
2117 /// * The user lacks the permission to change attributes of the file.
2124 /// fn main() -> std::io::Result<()> {
2125 /// let mut perms = fs::metadata("foo.txt")?.permissions();
2126 /// perms.set_readonly(true);
2127 /// fs::set_permissions("foo.txt", perms)?;
2131 #[stable(feature = "set_permissions", since = "1.1.0")]
2132 pub fn set_permissions<P: AsRef<Path>>(path: P, perm: Permissions) -> io::Result<()> {
2133 fs_imp::set_perm(path.as_ref(), perm.0)
2137 /// Creates a new set of options with default mode/security settings for all
2138 /// platforms and also non-recursive.
2143 /// use std::fs::DirBuilder;
2145 /// let builder = DirBuilder::new();
2147 #[stable(feature = "dir_builder", since = "1.6.0")]
2148 pub fn new() -> DirBuilder {
2149 DirBuilder { inner: fs_imp::DirBuilder::new(), recursive: false }
2152 /// Indicates that directories should be created recursively, creating all
2153 /// parent directories. Parents that do not exist are created with the same
2154 /// security and permissions settings.
2156 /// This option defaults to `false`.
2161 /// use std::fs::DirBuilder;
2163 /// let mut builder = DirBuilder::new();
2164 /// builder.recursive(true);
2166 #[stable(feature = "dir_builder", since = "1.6.0")]
2167 pub fn recursive(&mut self, recursive: bool) -> &mut Self {
2168 self.recursive = recursive;
2172 /// Creates the specified directory with the options configured in this
2175 /// It is considered an error if the directory already exists unless
2176 /// recursive mode is enabled.
2181 /// use std::fs::{self, DirBuilder};
2183 /// let path = "/tmp/foo/bar/baz";
2184 /// DirBuilder::new()
2185 /// .recursive(true)
2186 /// .create(path).unwrap();
2188 /// assert!(fs::metadata(path).unwrap().is_dir());
2190 #[stable(feature = "dir_builder", since = "1.6.0")]
2191 pub fn create<P: AsRef<Path>>(&self, path: P) -> io::Result<()> {
2192 self._create(path.as_ref())
2195 fn _create(&self, path: &Path) -> io::Result<()> {
2196 if self.recursive { self.create_dir_all(path) } else { self.inner.mkdir(path) }
2199 fn create_dir_all(&self, path: &Path) -> io::Result<()> {
2200 if path == Path::new("") {
2204 match self.inner.mkdir(path) {
2205 Ok(()) => return Ok(()),
2206 Err(ref e) if e.kind() == io::ErrorKind::NotFound => {}
2207 Err(_) if path.is_dir() => return Ok(()),
2208 Err(e) => return Err(e),
2210 match path.parent() {
2211 Some(p) => self.create_dir_all(p)?,
2213 return Err(io::Error::new(io::ErrorKind::Other, "failed to create whole tree"));
2216 match self.inner.mkdir(path) {
2218 Err(_) if path.is_dir() => Ok(()),
2224 impl AsInnerMut<fs_imp::DirBuilder> for DirBuilder {
2225 fn as_inner_mut(&mut self) -> &mut fs_imp::DirBuilder {
2230 #[cfg(all(test, not(any(target_os = "cloudabi", target_os = "emscripten", target_env = "sgx"))))]
2232 use crate::io::prelude::*;
2234 use crate::fs::{self, File, OpenOptions};
2235 use crate::io::{ErrorKind, SeekFrom};
2236 use crate::path::Path;
2238 use crate::sys_common::io::test::{tmpdir, TempDir};
2241 use rand::{rngs::StdRng, RngCore, SeedableRng};
2244 use crate::os::unix::fs::symlink as symlink_dir;
2246 use crate::os::unix::fs::symlink as symlink_file;
2248 use crate::os::unix::fs::symlink as symlink_junction;
2250 use crate::os::windows::fs::{symlink_dir, symlink_file};
2252 use crate::sys::fs::symlink_junction;
2254 macro_rules! check {
2258 Err(e) => panic!("{} failed with: {}", stringify!($e), e),
2264 macro_rules! error {
2265 ($e:expr, $s:expr) => {
2267 Ok(_) => panic!("Unexpected success. Should've been: {:?}", $s),
2268 Err(ref err) => assert!(
2269 err.raw_os_error() == Some($s),
2270 format!("`{}` did not have a code of `{}`", err, $s)
2277 macro_rules! error {
2278 ($e:expr, $s:expr) => {
2279 error_contains!($e, $s)
2283 macro_rules! error_contains {
2284 ($e:expr, $s:expr) => {
2286 Ok(_) => panic!("Unexpected success. Should've been: {:?}", $s),
2287 Err(ref err) => assert!(
2288 err.to_string().contains($s),
2289 format!("`{}` did not contain `{}`", err, $s)
2295 // Several test fail on windows if the user does not have permission to
2296 // create symlinks (the `SeCreateSymbolicLinkPrivilege`). Instead of
2297 // disabling these test on Windows, use this function to test whether we
2298 // have permission, and return otherwise. This way, we still don't run these
2299 // tests most of the time, but at least we do if the user has the right
2301 pub fn got_symlink_permission(tmpdir: &TempDir) -> bool {
2305 let link = tmpdir.join("some_hopefully_unique_link_name");
2307 match symlink_file(r"nonexisting_target", link) {
2309 // ERROR_PRIVILEGE_NOT_HELD = 1314
2310 Err(ref err) if err.raw_os_error() == Some(1314) => false,
2316 fn file_test_io_smoke_test() {
2317 let message = "it's alright. have a good time";
2318 let tmpdir = tmpdir();
2319 let filename = &tmpdir.join("file_rt_io_file_test.txt");
2321 let mut write_stream = check!(File::create(filename));
2322 check!(write_stream.write(message.as_bytes()));
2325 let mut read_stream = check!(File::open(filename));
2326 let mut read_buf = [0; 1028];
2327 let read_str = match check!(read_stream.read(&mut read_buf)) {
2328 0 => panic!("shouldn't happen"),
2329 n => str::from_utf8(&read_buf[..n]).unwrap().to_string(),
2331 assert_eq!(read_str, message);
2333 check!(fs::remove_file(filename));
2337 fn invalid_path_raises() {
2338 let tmpdir = tmpdir();
2339 let filename = &tmpdir.join("file_that_does_not_exist.txt");
2340 let result = File::open(filename);
2342 #[cfg(all(unix, not(target_os = "vxworks")))]
2343 error!(result, "No such file or directory");
2344 #[cfg(target_os = "vxworks")]
2345 error!(result, "no such file or directory");
2347 error!(result, 2); // ERROR_FILE_NOT_FOUND
2351 fn file_test_iounlinking_invalid_path_should_raise_condition() {
2352 let tmpdir = tmpdir();
2353 let filename = &tmpdir.join("file_another_file_that_does_not_exist.txt");
2355 let result = fs::remove_file(filename);
2357 #[cfg(all(unix, not(target_os = "vxworks")))]
2358 error!(result, "No such file or directory");
2359 #[cfg(target_os = "vxworks")]
2360 error!(result, "no such file or directory");
2362 error!(result, 2); // ERROR_FILE_NOT_FOUND
2366 fn file_test_io_non_positional_read() {
2367 let message: &str = "ten-four";
2368 let mut read_mem = [0; 8];
2369 let tmpdir = tmpdir();
2370 let filename = &tmpdir.join("file_rt_io_file_test_positional.txt");
2372 let mut rw_stream = check!(File::create(filename));
2373 check!(rw_stream.write(message.as_bytes()));
2376 let mut read_stream = check!(File::open(filename));
2378 let read_buf = &mut read_mem[0..4];
2379 check!(read_stream.read(read_buf));
2382 let read_buf = &mut read_mem[4..8];
2383 check!(read_stream.read(read_buf));
2386 check!(fs::remove_file(filename));
2387 let read_str = str::from_utf8(&read_mem).unwrap();
2388 assert_eq!(read_str, message);
2392 fn file_test_io_seek_and_tell_smoke_test() {
2393 let message = "ten-four";
2394 let mut read_mem = [0; 4];
2395 let set_cursor = 4 as u64;
2396 let tell_pos_pre_read;
2397 let tell_pos_post_read;
2398 let tmpdir = tmpdir();
2399 let filename = &tmpdir.join("file_rt_io_file_test_seeking.txt");
2401 let mut rw_stream = check!(File::create(filename));
2402 check!(rw_stream.write(message.as_bytes()));
2405 let mut read_stream = check!(File::open(filename));
2406 check!(read_stream.seek(SeekFrom::Start(set_cursor)));
2407 tell_pos_pre_read = check!(read_stream.seek(SeekFrom::Current(0)));
2408 check!(read_stream.read(&mut read_mem));
2409 tell_pos_post_read = check!(read_stream.seek(SeekFrom::Current(0)));
2411 check!(fs::remove_file(filename));
2412 let read_str = str::from_utf8(&read_mem).unwrap();
2413 assert_eq!(read_str, &message[4..8]);
2414 assert_eq!(tell_pos_pre_read, set_cursor);
2415 assert_eq!(tell_pos_post_read, message.len() as u64);
2419 fn file_test_io_seek_and_write() {
2420 let initial_msg = "food-is-yummy";
2421 let overwrite_msg = "-the-bar!!";
2422 let final_msg = "foo-the-bar!!";
2424 let mut read_mem = [0; 13];
2425 let tmpdir = tmpdir();
2426 let filename = &tmpdir.join("file_rt_io_file_test_seek_and_write.txt");
2428 let mut rw_stream = check!(File::create(filename));
2429 check!(rw_stream.write(initial_msg.as_bytes()));
2430 check!(rw_stream.seek(SeekFrom::Start(seek_idx)));
2431 check!(rw_stream.write(overwrite_msg.as_bytes()));
2434 let mut read_stream = check!(File::open(filename));
2435 check!(read_stream.read(&mut read_mem));
2437 check!(fs::remove_file(filename));
2438 let read_str = str::from_utf8(&read_mem).unwrap();
2439 assert!(read_str == final_msg);
2443 fn file_test_io_seek_shakedown() {
2445 let initial_msg = "qwer-asdf-zxcv";
2446 let chunk_one: &str = "qwer";
2447 let chunk_two: &str = "asdf";
2448 let chunk_three: &str = "zxcv";
2449 let mut read_mem = [0; 4];
2450 let tmpdir = tmpdir();
2451 let filename = &tmpdir.join("file_rt_io_file_test_seek_shakedown.txt");
2453 let mut rw_stream = check!(File::create(filename));
2454 check!(rw_stream.write(initial_msg.as_bytes()));
2457 let mut read_stream = check!(File::open(filename));
2459 check!(read_stream.seek(SeekFrom::End(-4)));
2460 check!(read_stream.read(&mut read_mem));
2461 assert_eq!(str::from_utf8(&read_mem).unwrap(), chunk_three);
2463 check!(read_stream.seek(SeekFrom::Current(-9)));
2464 check!(read_stream.read(&mut read_mem));
2465 assert_eq!(str::from_utf8(&read_mem).unwrap(), chunk_two);
2467 check!(read_stream.seek(SeekFrom::Start(0)));
2468 check!(read_stream.read(&mut read_mem));
2469 assert_eq!(str::from_utf8(&read_mem).unwrap(), chunk_one);
2471 check!(fs::remove_file(filename));
2475 fn file_test_io_eof() {
2476 let tmpdir = tmpdir();
2477 let filename = tmpdir.join("file_rt_io_file_test_eof.txt");
2478 let mut buf = [0; 256];
2480 let oo = OpenOptions::new().create_new(true).write(true).read(true).clone();
2481 let mut rw = check!(oo.open(&filename));
2482 assert_eq!(check!(rw.read(&mut buf)), 0);
2483 assert_eq!(check!(rw.read(&mut buf)), 0);
2485 check!(fs::remove_file(&filename));
2490 fn file_test_io_read_write_at() {
2491 use crate::os::unix::fs::FileExt;
2493 let tmpdir = tmpdir();
2494 let filename = tmpdir.join("file_rt_io_file_test_read_write_at.txt");
2495 let mut buf = [0; 256];
2496 let write1 = "asdf";
2497 let write2 = "qwer-";
2498 let write3 = "-zxcv";
2499 let content = "qwer-asdf-zxcv";
2501 let oo = OpenOptions::new().create_new(true).write(true).read(true).clone();
2502 let mut rw = check!(oo.open(&filename));
2503 assert_eq!(check!(rw.write_at(write1.as_bytes(), 5)), write1.len());
2504 assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 0);
2505 assert_eq!(check!(rw.read_at(&mut buf, 5)), write1.len());
2506 assert_eq!(str::from_utf8(&buf[..write1.len()]), Ok(write1));
2507 assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 0);
2508 assert_eq!(check!(rw.read_at(&mut buf[..write2.len()], 0)), write2.len());
2509 assert_eq!(str::from_utf8(&buf[..write2.len()]), Ok("\0\0\0\0\0"));
2510 assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 0);
2511 assert_eq!(check!(rw.write(write2.as_bytes())), write2.len());
2512 assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 5);
2513 assert_eq!(check!(rw.read(&mut buf)), write1.len());
2514 assert_eq!(str::from_utf8(&buf[..write1.len()]), Ok(write1));
2515 assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 9);
2516 assert_eq!(check!(rw.read_at(&mut buf[..write2.len()], 0)), write2.len());
2517 assert_eq!(str::from_utf8(&buf[..write2.len()]), Ok(write2));
2518 assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 9);
2519 assert_eq!(check!(rw.write_at(write3.as_bytes(), 9)), write3.len());
2520 assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 9);
2523 let mut read = check!(File::open(&filename));
2524 assert_eq!(check!(read.read_at(&mut buf, 0)), content.len());
2525 assert_eq!(str::from_utf8(&buf[..content.len()]), Ok(content));
2526 assert_eq!(check!(read.seek(SeekFrom::Current(0))), 0);
2527 assert_eq!(check!(read.seek(SeekFrom::End(-5))), 9);
2528 assert_eq!(check!(read.read_at(&mut buf, 0)), content.len());
2529 assert_eq!(str::from_utf8(&buf[..content.len()]), Ok(content));
2530 assert_eq!(check!(read.seek(SeekFrom::Current(0))), 9);
2531 assert_eq!(check!(read.read(&mut buf)), write3.len());
2532 assert_eq!(str::from_utf8(&buf[..write3.len()]), Ok(write3));
2533 assert_eq!(check!(read.seek(SeekFrom::Current(0))), 14);
2534 assert_eq!(check!(read.read_at(&mut buf, 0)), content.len());
2535 assert_eq!(str::from_utf8(&buf[..content.len()]), Ok(content));
2536 assert_eq!(check!(read.seek(SeekFrom::Current(0))), 14);
2537 assert_eq!(check!(read.read_at(&mut buf, 14)), 0);
2538 assert_eq!(check!(read.read_at(&mut buf, 15)), 0);
2539 assert_eq!(check!(read.seek(SeekFrom::Current(0))), 14);
2541 check!(fs::remove_file(&filename));
2546 fn set_get_unix_permissions() {
2547 use crate::os::unix::fs::PermissionsExt;
2549 let tmpdir = tmpdir();
2550 let filename = &tmpdir.join("set_get_unix_permissions");
2551 check!(fs::create_dir(filename));
2554 check!(fs::set_permissions(filename, fs::Permissions::from_mode(0)));
2555 let metadata0 = check!(fs::metadata(filename));
2556 assert_eq!(mask & metadata0.permissions().mode(), 0);
2558 check!(fs::set_permissions(filename, fs::Permissions::from_mode(0o1777)));
2559 let metadata1 = check!(fs::metadata(filename));
2560 #[cfg(all(unix, not(target_os = "vxworks")))]
2561 assert_eq!(mask & metadata1.permissions().mode(), 0o1777);
2562 #[cfg(target_os = "vxworks")]
2563 assert_eq!(mask & metadata1.permissions().mode(), 0o0777);
2568 fn file_test_io_seek_read_write() {
2569 use crate::os::windows::fs::FileExt;
2571 let tmpdir = tmpdir();
2572 let filename = tmpdir.join("file_rt_io_file_test_seek_read_write.txt");
2573 let mut buf = [0; 256];
2574 let write1 = "asdf";
2575 let write2 = "qwer-";
2576 let write3 = "-zxcv";
2577 let content = "qwer-asdf-zxcv";
2579 let oo = OpenOptions::new().create_new(true).write(true).read(true).clone();
2580 let mut rw = check!(oo.open(&filename));
2581 assert_eq!(check!(rw.seek_write(write1.as_bytes(), 5)), write1.len());
2582 assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 9);
2583 assert_eq!(check!(rw.seek_read(&mut buf, 5)), write1.len());
2584 assert_eq!(str::from_utf8(&buf[..write1.len()]), Ok(write1));
2585 assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 9);
2586 assert_eq!(check!(rw.seek(SeekFrom::Start(0))), 0);
2587 assert_eq!(check!(rw.write(write2.as_bytes())), write2.len());
2588 assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 5);
2589 assert_eq!(check!(rw.read(&mut buf)), write1.len());
2590 assert_eq!(str::from_utf8(&buf[..write1.len()]), Ok(write1));
2591 assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 9);
2592 assert_eq!(check!(rw.seek_read(&mut buf[..write2.len()], 0)), write2.len());
2593 assert_eq!(str::from_utf8(&buf[..write2.len()]), Ok(write2));
2594 assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 5);
2595 assert_eq!(check!(rw.seek_write(write3.as_bytes(), 9)), write3.len());
2596 assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 14);
2599 let mut read = check!(File::open(&filename));
2600 assert_eq!(check!(read.seek_read(&mut buf, 0)), content.len());
2601 assert_eq!(str::from_utf8(&buf[..content.len()]), Ok(content));
2602 assert_eq!(check!(read.seek(SeekFrom::Current(0))), 14);
2603 assert_eq!(check!(read.seek(SeekFrom::End(-5))), 9);
2604 assert_eq!(check!(read.seek_read(&mut buf, 0)), content.len());
2605 assert_eq!(str::from_utf8(&buf[..content.len()]), Ok(content));
2606 assert_eq!(check!(read.seek(SeekFrom::Current(0))), 14);
2607 assert_eq!(check!(read.seek(SeekFrom::End(-5))), 9);
2608 assert_eq!(check!(read.read(&mut buf)), write3.len());
2609 assert_eq!(str::from_utf8(&buf[..write3.len()]), Ok(write3));
2610 assert_eq!(check!(read.seek(SeekFrom::Current(0))), 14);
2611 assert_eq!(check!(read.seek_read(&mut buf, 0)), content.len());
2612 assert_eq!(str::from_utf8(&buf[..content.len()]), Ok(content));
2613 assert_eq!(check!(read.seek(SeekFrom::Current(0))), 14);
2614 assert_eq!(check!(read.seek_read(&mut buf, 14)), 0);
2615 assert_eq!(check!(read.seek_read(&mut buf, 15)), 0);
2617 check!(fs::remove_file(&filename));
2621 fn file_test_stat_is_correct_on_is_file() {
2622 let tmpdir = tmpdir();
2623 let filename = &tmpdir.join("file_stat_correct_on_is_file.txt");
2625 let mut opts = OpenOptions::new();
2626 let mut fs = check!(opts.read(true).write(true).create(true).open(filename));
2628 fs.write(msg.as_bytes()).unwrap();
2630 let fstat_res = check!(fs.metadata());
2631 assert!(fstat_res.is_file());
2633 let stat_res_fn = check!(fs::metadata(filename));
2634 assert!(stat_res_fn.is_file());
2635 let stat_res_meth = check!(filename.metadata());
2636 assert!(stat_res_meth.is_file());
2637 check!(fs::remove_file(filename));
2641 fn file_test_stat_is_correct_on_is_dir() {
2642 let tmpdir = tmpdir();
2643 let filename = &tmpdir.join("file_stat_correct_on_is_dir");
2644 check!(fs::create_dir(filename));
2645 let stat_res_fn = check!(fs::metadata(filename));
2646 assert!(stat_res_fn.is_dir());
2647 let stat_res_meth = check!(filename.metadata());
2648 assert!(stat_res_meth.is_dir());
2649 check!(fs::remove_dir(filename));
2653 fn file_test_fileinfo_false_when_checking_is_file_on_a_directory() {
2654 let tmpdir = tmpdir();
2655 let dir = &tmpdir.join("fileinfo_false_on_dir");
2656 check!(fs::create_dir(dir));
2657 assert!(!dir.is_file());
2658 check!(fs::remove_dir(dir));
2662 fn file_test_fileinfo_check_exists_before_and_after_file_creation() {
2663 let tmpdir = tmpdir();
2664 let file = &tmpdir.join("fileinfo_check_exists_b_and_a.txt");
2665 check!(check!(File::create(file)).write(b"foo"));
2666 assert!(file.exists());
2667 check!(fs::remove_file(file));
2668 assert!(!file.exists());
2672 fn file_test_directoryinfo_check_exists_before_and_after_mkdir() {
2673 let tmpdir = tmpdir();
2674 let dir = &tmpdir.join("before_and_after_dir");
2675 assert!(!dir.exists());
2676 check!(fs::create_dir(dir));
2677 assert!(dir.exists());
2678 assert!(dir.is_dir());
2679 check!(fs::remove_dir(dir));
2680 assert!(!dir.exists());
2684 fn file_test_directoryinfo_readdir() {
2685 let tmpdir = tmpdir();
2686 let dir = &tmpdir.join("di_readdir");
2687 check!(fs::create_dir(dir));
2690 let f = dir.join(&format!("{}.txt", n));
2691 let mut w = check!(File::create(&f));
2692 let msg_str = format!("{}{}", prefix, n.to_string());
2693 let msg = msg_str.as_bytes();
2694 check!(w.write(msg));
2696 let files = check!(fs::read_dir(dir));
2697 let mut mem = [0; 4];
2699 let f = f.unwrap().path();
2701 let n = f.file_stem().unwrap();
2702 check!(check!(File::open(&f)).read(&mut mem));
2703 let read_str = str::from_utf8(&mem).unwrap();
2704 let expected = format!("{}{}", prefix, n.to_str().unwrap());
2705 assert_eq!(expected, read_str);
2707 check!(fs::remove_file(&f));
2709 check!(fs::remove_dir(dir));
2713 fn file_create_new_already_exists_error() {
2714 let tmpdir = tmpdir();
2715 let file = &tmpdir.join("file_create_new_error_exists");
2716 check!(fs::File::create(file));
2717 let e = fs::OpenOptions::new().write(true).create_new(true).open(file).unwrap_err();
2718 assert_eq!(e.kind(), ErrorKind::AlreadyExists);
2722 fn mkdir_path_already_exists_error() {
2723 let tmpdir = tmpdir();
2724 let dir = &tmpdir.join("mkdir_error_twice");
2725 check!(fs::create_dir(dir));
2726 let e = fs::create_dir(dir).unwrap_err();
2727 assert_eq!(e.kind(), ErrorKind::AlreadyExists);
2731 fn recursive_mkdir() {
2732 let tmpdir = tmpdir();
2733 let dir = tmpdir.join("d1/d2");
2734 check!(fs::create_dir_all(&dir));
2735 assert!(dir.is_dir())
2739 fn recursive_mkdir_failure() {
2740 let tmpdir = tmpdir();
2741 let dir = tmpdir.join("d1");
2742 let file = dir.join("f1");
2744 check!(fs::create_dir_all(&dir));
2745 check!(File::create(&file));
2747 let result = fs::create_dir_all(&file);
2749 assert!(result.is_err());
2753 fn concurrent_recursive_mkdir() {
2756 let mut dir = dir.join("a");
2758 dir = dir.join("a");
2760 let mut join = vec![];
2762 let dir = dir.clone();
2763 join.push(thread::spawn(move || {
2764 check!(fs::create_dir_all(&dir));
2768 // No `Display` on result of `join()`
2769 join.drain(..).map(|join| join.join().unwrap()).count();
2774 fn recursive_mkdir_slash() {
2775 check!(fs::create_dir_all(Path::new("/")));
2779 fn recursive_mkdir_dot() {
2780 check!(fs::create_dir_all(Path::new(".")));
2784 fn recursive_mkdir_empty() {
2785 check!(fs::create_dir_all(Path::new("")));
2789 fn recursive_rmdir() {
2790 let tmpdir = tmpdir();
2791 let d1 = tmpdir.join("d1");
2792 let dt = d1.join("t");
2793 let dtt = dt.join("t");
2794 let d2 = tmpdir.join("d2");
2795 let canary = d2.join("do_not_delete");
2796 check!(fs::create_dir_all(&dtt));
2797 check!(fs::create_dir_all(&d2));
2798 check!(check!(File::create(&canary)).write(b"foo"));
2799 check!(symlink_junction(&d2, &dt.join("d2")));
2800 let _ = symlink_file(&canary, &d1.join("canary"));
2801 check!(fs::remove_dir_all(&d1));
2803 assert!(!d1.is_dir());
2804 assert!(canary.exists());
2808 fn recursive_rmdir_of_symlink() {
2809 // test we do not recursively delete a symlink but only dirs.
2810 let tmpdir = tmpdir();
2811 let link = tmpdir.join("d1");
2812 let dir = tmpdir.join("d2");
2813 let canary = dir.join("do_not_delete");
2814 check!(fs::create_dir_all(&dir));
2815 check!(check!(File::create(&canary)).write(b"foo"));
2816 check!(symlink_junction(&dir, &link));
2817 check!(fs::remove_dir_all(&link));
2819 assert!(!link.is_dir());
2820 assert!(canary.exists());
2824 // only Windows makes a distinction between file and directory symlinks.
2826 fn recursive_rmdir_of_file_symlink() {
2827 let tmpdir = tmpdir();
2828 if !got_symlink_permission(&tmpdir) {
2832 let f1 = tmpdir.join("f1");
2833 let f2 = tmpdir.join("f2");
2834 check!(check!(File::create(&f1)).write(b"foo"));
2835 check!(symlink_file(&f1, &f2));
2836 match fs::remove_dir_all(&f2) {
2837 Ok(..) => panic!("wanted a failure"),
2843 fn unicode_path_is_dir() {
2844 assert!(Path::new(".").is_dir());
2845 assert!(!Path::new("test/stdtest/fs.rs").is_dir());
2847 let tmpdir = tmpdir();
2849 let mut dirpath = tmpdir.path().to_path_buf();
2850 dirpath.push("test-가一ー你好");
2851 check!(fs::create_dir(&dirpath));
2852 assert!(dirpath.is_dir());
2854 let mut filepath = dirpath;
2855 filepath.push("unicode-file-\u{ac00}\u{4e00}\u{30fc}\u{4f60}\u{597d}.rs");
2856 check!(File::create(&filepath)); // ignore return; touch only
2857 assert!(!filepath.is_dir());
2858 assert!(filepath.exists());
2862 fn unicode_path_exists() {
2863 assert!(Path::new(".").exists());
2864 assert!(!Path::new("test/nonexistent-bogus-path").exists());
2866 let tmpdir = tmpdir();
2867 let unicode = tmpdir.path();
2868 let unicode = unicode.join("test-각丁ー再见");
2869 check!(fs::create_dir(&unicode));
2870 assert!(unicode.exists());
2871 assert!(!Path::new("test/unicode-bogus-path-각丁ー再见").exists());
2875 fn copy_file_does_not_exist() {
2876 let from = Path::new("test/nonexistent-bogus-path");
2877 let to = Path::new("test/other-bogus-path");
2879 match fs::copy(&from, &to) {
2882 assert!(!from.exists());
2883 assert!(!to.exists());
2889 fn copy_src_does_not_exist() {
2890 let tmpdir = tmpdir();
2891 let from = Path::new("test/nonexistent-bogus-path");
2892 let to = tmpdir.join("out.txt");
2893 check!(check!(File::create(&to)).write(b"hello"));
2894 assert!(fs::copy(&from, &to).is_err());
2895 assert!(!from.exists());
2896 let mut v = Vec::new();
2897 check!(check!(File::open(&to)).read_to_end(&mut v));
2898 assert_eq!(v, b"hello");
2903 let tmpdir = tmpdir();
2904 let input = tmpdir.join("in.txt");
2905 let out = tmpdir.join("out.txt");
2907 check!(check!(File::create(&input)).write(b"hello"));
2908 check!(fs::copy(&input, &out));
2909 let mut v = Vec::new();
2910 check!(check!(File::open(&out)).read_to_end(&mut v));
2911 assert_eq!(v, b"hello");
2913 assert_eq!(check!(input.metadata()).permissions(), check!(out.metadata()).permissions());
2917 fn copy_file_dst_dir() {
2918 let tmpdir = tmpdir();
2919 let out = tmpdir.join("out");
2921 check!(File::create(&out));
2922 match fs::copy(&*out, tmpdir.path()) {
2929 fn copy_file_dst_exists() {
2930 let tmpdir = tmpdir();
2931 let input = tmpdir.join("in");
2932 let output = tmpdir.join("out");
2934 check!(check!(File::create(&input)).write("foo".as_bytes()));
2935 check!(check!(File::create(&output)).write("bar".as_bytes()));
2936 check!(fs::copy(&input, &output));
2938 let mut v = Vec::new();
2939 check!(check!(File::open(&output)).read_to_end(&mut v));
2940 assert_eq!(v, b"foo".to_vec());
2944 fn copy_file_src_dir() {
2945 let tmpdir = tmpdir();
2946 let out = tmpdir.join("out");
2948 match fs::copy(tmpdir.path(), &out) {
2952 assert!(!out.exists());
2956 fn copy_file_preserves_perm_bits() {
2957 let tmpdir = tmpdir();
2958 let input = tmpdir.join("in.txt");
2959 let out = tmpdir.join("out.txt");
2961 let attr = check!(check!(File::create(&input)).metadata());
2962 let mut p = attr.permissions();
2963 p.set_readonly(true);
2964 check!(fs::set_permissions(&input, p));
2965 check!(fs::copy(&input, &out));
2966 assert!(check!(out.metadata()).permissions().readonly());
2967 check!(fs::set_permissions(&input, attr.permissions()));
2968 check!(fs::set_permissions(&out, attr.permissions()));
2973 fn copy_file_preserves_streams() {
2975 check!(check!(File::create(tmp.join("in.txt:bunny"))).write("carrot".as_bytes()));
2976 assert_eq!(check!(fs::copy(tmp.join("in.txt"), tmp.join("out.txt"))), 0);
2977 assert_eq!(check!(tmp.join("out.txt").metadata()).len(), 0);
2978 let mut v = Vec::new();
2979 check!(check!(File::open(tmp.join("out.txt:bunny"))).read_to_end(&mut v));
2980 assert_eq!(v, b"carrot".to_vec());
2984 fn copy_file_returns_metadata_len() {
2986 let in_path = tmp.join("in.txt");
2987 let out_path = tmp.join("out.txt");
2988 check!(check!(File::create(&in_path)).write(b"lettuce"));
2990 check!(check!(File::create(tmp.join("in.txt:bunny"))).write(b"carrot"));
2991 let copied_len = check!(fs::copy(&in_path, &out_path));
2992 assert_eq!(check!(out_path.metadata()).len(), copied_len);
2996 fn copy_file_follows_dst_symlink() {
2998 if !got_symlink_permission(&tmp) {
3002 let in_path = tmp.join("in.txt");
3003 let out_path = tmp.join("out.txt");
3004 let out_path_symlink = tmp.join("out_symlink.txt");
3006 check!(fs::write(&in_path, "foo"));
3007 check!(fs::write(&out_path, "bar"));
3008 check!(symlink_file(&out_path, &out_path_symlink));
3010 check!(fs::copy(&in_path, &out_path_symlink));
3012 assert!(check!(out_path_symlink.symlink_metadata()).file_type().is_symlink());
3013 assert_eq!(check!(fs::read(&out_path_symlink)), b"foo".to_vec());
3014 assert_eq!(check!(fs::read(&out_path)), b"foo".to_vec());
3018 fn symlinks_work() {
3019 let tmpdir = tmpdir();
3020 if !got_symlink_permission(&tmpdir) {
3024 let input = tmpdir.join("in.txt");
3025 let out = tmpdir.join("out.txt");
3027 check!(check!(File::create(&input)).write("foobar".as_bytes()));
3028 check!(symlink_file(&input, &out));
3029 assert!(check!(out.symlink_metadata()).file_type().is_symlink());
3030 assert_eq!(check!(fs::metadata(&out)).len(), check!(fs::metadata(&input)).len());
3031 let mut v = Vec::new();
3032 check!(check!(File::open(&out)).read_to_end(&mut v));
3033 assert_eq!(v, b"foobar".to_vec());
3037 fn symlink_noexist() {
3038 // Symlinks can point to things that don't exist
3039 let tmpdir = tmpdir();
3040 if !got_symlink_permission(&tmpdir) {
3044 // Use a relative path for testing. Symlinks get normalized by Windows,
3045 // so we may not get the same path back for absolute paths
3046 check!(symlink_file(&"foo", &tmpdir.join("bar")));
3047 assert_eq!(check!(fs::read_link(&tmpdir.join("bar"))).to_str().unwrap(), "foo");
3053 // directory symlink
3055 check!(fs::read_link(r"C:\Users\All Users")).to_str().unwrap(),
3060 check!(fs::read_link(r"C:\Users\Default User")).to_str().unwrap(),
3063 // junction with special permissions
3065 check!(fs::read_link(r"C:\Documents and Settings\")).to_str().unwrap(),
3069 let tmpdir = tmpdir();
3070 let link = tmpdir.join("link");
3071 if !got_symlink_permission(&tmpdir) {
3074 check!(symlink_file(&"foo", &link));
3075 assert_eq!(check!(fs::read_link(&link)).to_str().unwrap(), "foo");
3079 fn readlink_not_symlink() {
3080 let tmpdir = tmpdir();
3081 match fs::read_link(tmpdir.path()) {
3082 Ok(..) => panic!("wanted a failure"),
3089 let tmpdir = tmpdir();
3090 let input = tmpdir.join("in.txt");
3091 let out = tmpdir.join("out.txt");
3093 check!(check!(File::create(&input)).write("foobar".as_bytes()));
3094 check!(fs::hard_link(&input, &out));
3095 assert_eq!(check!(fs::metadata(&out)).len(), check!(fs::metadata(&input)).len());
3096 assert_eq!(check!(fs::metadata(&out)).len(), check!(input.metadata()).len());
3097 let mut v = Vec::new();
3098 check!(check!(File::open(&out)).read_to_end(&mut v));
3099 assert_eq!(v, b"foobar".to_vec());
3101 // can't link to yourself
3102 match fs::hard_link(&input, &input) {
3103 Ok(..) => panic!("wanted a failure"),
3106 // can't link to something that doesn't exist
3107 match fs::hard_link(&tmpdir.join("foo"), &tmpdir.join("bar")) {
3108 Ok(..) => panic!("wanted a failure"),
3115 let tmpdir = tmpdir();
3116 let file = tmpdir.join("in.txt");
3118 check!(File::create(&file));
3119 let attr = check!(fs::metadata(&file));
3120 assert!(!attr.permissions().readonly());
3121 let mut p = attr.permissions();
3122 p.set_readonly(true);
3123 check!(fs::set_permissions(&file, p.clone()));
3124 let attr = check!(fs::metadata(&file));
3125 assert!(attr.permissions().readonly());
3127 match fs::set_permissions(&tmpdir.join("foo"), p.clone()) {
3128 Ok(..) => panic!("wanted an error"),
3132 p.set_readonly(false);
3133 check!(fs::set_permissions(&file, p));
3138 let tmpdir = tmpdir();
3139 let path = tmpdir.join("in.txt");
3141 let file = check!(File::create(&path));
3142 let attr = check!(fs::metadata(&path));
3143 assert!(!attr.permissions().readonly());
3144 let mut p = attr.permissions();
3145 p.set_readonly(true);
3146 check!(file.set_permissions(p.clone()));
3147 let attr = check!(fs::metadata(&path));
3148 assert!(attr.permissions().readonly());
3150 p.set_readonly(false);
3151 check!(file.set_permissions(p));
3155 fn sync_doesnt_kill_anything() {
3156 let tmpdir = tmpdir();
3157 let path = tmpdir.join("in.txt");
3159 let mut file = check!(File::create(&path));
3160 check!(file.sync_all());
3161 check!(file.sync_data());
3162 check!(file.write(b"foo"));
3163 check!(file.sync_all());
3164 check!(file.sync_data());
3168 fn truncate_works() {
3169 let tmpdir = tmpdir();
3170 let path = tmpdir.join("in.txt");
3172 let mut file = check!(File::create(&path));
3173 check!(file.write(b"foo"));
3174 check!(file.sync_all());
3176 // Do some simple things with truncation
3177 assert_eq!(check!(file.metadata()).len(), 3);
3178 check!(file.set_len(10));
3179 assert_eq!(check!(file.metadata()).len(), 10);
3180 check!(file.write(b"bar"));
3181 check!(file.sync_all());
3182 assert_eq!(check!(file.metadata()).len(), 10);
3184 let mut v = Vec::new();
3185 check!(check!(File::open(&path)).read_to_end(&mut v));
3186 assert_eq!(v, b"foobar\0\0\0\0".to_vec());
3188 // Truncate to a smaller length, don't seek, and then write something.
3189 // Ensure that the intermediate zeroes are all filled in (we have `seek`ed
3190 // past the end of the file).
3191 check!(file.set_len(2));
3192 assert_eq!(check!(file.metadata()).len(), 2);
3193 check!(file.write(b"wut"));
3194 check!(file.sync_all());
3195 assert_eq!(check!(file.metadata()).len(), 9);
3196 let mut v = Vec::new();
3197 check!(check!(File::open(&path)).read_to_end(&mut v));
3198 assert_eq!(v, b"fo\0\0\0\0wut".to_vec());
3203 use crate::fs::OpenOptions as OO;
3204 fn c<T: Clone>(t: &T) -> T {
3208 let tmpdir = tmpdir();
3210 let mut r = OO::new();
3212 let mut w = OO::new();
3214 let mut rw = OO::new();
3215 rw.read(true).write(true);
3216 let mut a = OO::new();
3218 let mut ra = OO::new();
3219 ra.read(true).append(true);
3222 let invalid_options = 87; // ERROR_INVALID_PARAMETER
3223 #[cfg(all(unix, not(target_os = "vxworks")))]
3224 let invalid_options = "Invalid argument";
3225 #[cfg(target_os = "vxworks")]
3226 let invalid_options = "invalid argument";
3228 // Test various combinations of creation modes and access modes.
3231 // creation mode | read | write | read-write | append | read-append |
3232 // :-----------------------|:-----:|:-----:|:----------:|:------:|:-----------:|
3233 // not set (open existing) | X | X | X | X | X |
3234 // create | | X | X | X | X |
3235 // truncate | | X | X | | |
3236 // create and truncate | | X | X | | |
3237 // create_new | | X | X | X | X |
3239 // tested in reverse order, so 'create_new' creates the file, and 'open existing' opens it.
3242 check!(c(&w).create_new(true).open(&tmpdir.join("a")));
3243 check!(c(&w).create(true).truncate(true).open(&tmpdir.join("a")));
3244 check!(c(&w).truncate(true).open(&tmpdir.join("a")));
3245 check!(c(&w).create(true).open(&tmpdir.join("a")));
3246 check!(c(&w).open(&tmpdir.join("a")));
3249 error!(c(&r).create_new(true).open(&tmpdir.join("b")), invalid_options);
3250 error!(c(&r).create(true).truncate(true).open(&tmpdir.join("b")), invalid_options);
3251 error!(c(&r).truncate(true).open(&tmpdir.join("b")), invalid_options);
3252 error!(c(&r).create(true).open(&tmpdir.join("b")), invalid_options);
3253 check!(c(&r).open(&tmpdir.join("a"))); // try opening the file created with write_only
3256 check!(c(&rw).create_new(true).open(&tmpdir.join("c")));
3257 check!(c(&rw).create(true).truncate(true).open(&tmpdir.join("c")));
3258 check!(c(&rw).truncate(true).open(&tmpdir.join("c")));
3259 check!(c(&rw).create(true).open(&tmpdir.join("c")));
3260 check!(c(&rw).open(&tmpdir.join("c")));
3263 check!(c(&a).create_new(true).open(&tmpdir.join("d")));
3264 error!(c(&a).create(true).truncate(true).open(&tmpdir.join("d")), invalid_options);
3265 error!(c(&a).truncate(true).open(&tmpdir.join("d")), invalid_options);
3266 check!(c(&a).create(true).open(&tmpdir.join("d")));
3267 check!(c(&a).open(&tmpdir.join("d")));
3270 check!(c(&ra).create_new(true).open(&tmpdir.join("e")));
3271 error!(c(&ra).create(true).truncate(true).open(&tmpdir.join("e")), invalid_options);
3272 error!(c(&ra).truncate(true).open(&tmpdir.join("e")), invalid_options);
3273 check!(c(&ra).create(true).open(&tmpdir.join("e")));
3274 check!(c(&ra).open(&tmpdir.join("e")));
3276 // Test opening a file without setting an access mode
3277 let mut blank = OO::new();
3278 error!(blank.create(true).open(&tmpdir.join("f")), invalid_options);
3281 check!(check!(File::create(&tmpdir.join("h"))).write("foobar".as_bytes()));
3283 // Test write fails for read-only
3284 check!(r.open(&tmpdir.join("h")));
3286 let mut f = check!(r.open(&tmpdir.join("h")));
3287 assert!(f.write("wut".as_bytes()).is_err());
3290 // Test write overwrites
3292 let mut f = check!(c(&w).open(&tmpdir.join("h")));
3293 check!(f.write("baz".as_bytes()));
3296 let mut f = check!(c(&r).open(&tmpdir.join("h")));
3297 let mut b = vec![0; 6];
3298 check!(f.read(&mut b));
3299 assert_eq!(b, "bazbar".as_bytes());
3302 // Test truncate works
3304 let mut f = check!(c(&w).truncate(true).open(&tmpdir.join("h")));
3305 check!(f.write("foo".as_bytes()));
3307 assert_eq!(check!(fs::metadata(&tmpdir.join("h"))).len(), 3);
3309 // Test append works
3310 assert_eq!(check!(fs::metadata(&tmpdir.join("h"))).len(), 3);
3312 let mut f = check!(c(&a).open(&tmpdir.join("h")));
3313 check!(f.write("bar".as_bytes()));
3315 assert_eq!(check!(fs::metadata(&tmpdir.join("h"))).len(), 6);
3317 // Test .append(true) equals .write(true).append(true)
3319 let mut f = check!(c(&w).append(true).open(&tmpdir.join("h")));
3320 check!(f.write("baz".as_bytes()));
3322 assert_eq!(check!(fs::metadata(&tmpdir.join("h"))).len(), 9);
3326 fn _assert_send_sync() {
3327 fn _assert_send_sync<T: Send + Sync>() {}
3328 _assert_send_sync::<OpenOptions>();
3333 let mut bytes = [0; 1024];
3334 StdRng::from_entropy().fill_bytes(&mut bytes);
3336 let tmpdir = tmpdir();
3338 check!(check!(File::create(&tmpdir.join("test"))).write(&bytes));
3339 let mut v = Vec::new();
3340 check!(check!(File::open(&tmpdir.join("test"))).read_to_end(&mut v));
3341 assert!(v == &bytes[..]);
3345 fn write_then_read() {
3346 let mut bytes = [0; 1024];
3347 StdRng::from_entropy().fill_bytes(&mut bytes);
3349 let tmpdir = tmpdir();
3351 check!(fs::write(&tmpdir.join("test"), &bytes[..]));
3352 let v = check!(fs::read(&tmpdir.join("test")));
3353 assert!(v == &bytes[..]);
3355 check!(fs::write(&tmpdir.join("not-utf8"), &[0xFF]));
3357 fs::read_to_string(&tmpdir.join("not-utf8")),
3358 "stream did not contain valid UTF-8"
3362 check!(fs::write(&tmpdir.join("utf8"), s.as_bytes()));
3363 let string = check!(fs::read_to_string(&tmpdir.join("utf8")));
3364 assert_eq!(string, s);
3368 fn file_try_clone() {
3369 let tmpdir = tmpdir();
3371 let mut f1 = check!(
3372 OpenOptions::new().read(true).write(true).create(true).open(&tmpdir.join("test"))
3374 let mut f2 = check!(f1.try_clone());
3376 check!(f1.write_all(b"hello world"));
3377 check!(f1.seek(SeekFrom::Start(2)));
3379 let mut buf = vec![];
3380 check!(f2.read_to_end(&mut buf));
3381 assert_eq!(buf, b"llo world");
3384 check!(f1.write_all(b"!"));
3388 #[cfg(not(windows))]
3389 fn unlink_readonly() {
3390 let tmpdir = tmpdir();
3391 let path = tmpdir.join("file");
3392 check!(File::create(&path));
3393 let mut perm = check!(fs::metadata(&path)).permissions();
3394 perm.set_readonly(true);
3395 check!(fs::set_permissions(&path, perm));
3396 check!(fs::remove_file(&path));
3400 fn mkdir_trailing_slash() {
3401 let tmpdir = tmpdir();
3402 let path = tmpdir.join("file");
3403 check!(fs::create_dir_all(&path.join("a/")));
3407 fn canonicalize_works_simple() {
3408 let tmpdir = tmpdir();
3409 let tmpdir = fs::canonicalize(tmpdir.path()).unwrap();
3410 let file = tmpdir.join("test");
3411 File::create(&file).unwrap();
3412 assert_eq!(fs::canonicalize(&file).unwrap(), file);
3416 fn realpath_works() {
3417 let tmpdir = tmpdir();
3418 if !got_symlink_permission(&tmpdir) {
3422 let tmpdir = fs::canonicalize(tmpdir.path()).unwrap();
3423 let file = tmpdir.join("test");
3424 let dir = tmpdir.join("test2");
3425 let link = dir.join("link");
3426 let linkdir = tmpdir.join("test3");
3428 File::create(&file).unwrap();
3429 fs::create_dir(&dir).unwrap();
3430 symlink_file(&file, &link).unwrap();
3431 symlink_dir(&dir, &linkdir).unwrap();
3433 assert!(link.symlink_metadata().unwrap().file_type().is_symlink());
3435 assert_eq!(fs::canonicalize(&tmpdir).unwrap(), tmpdir);
3436 assert_eq!(fs::canonicalize(&file).unwrap(), file);
3437 assert_eq!(fs::canonicalize(&link).unwrap(), file);
3438 assert_eq!(fs::canonicalize(&linkdir).unwrap(), dir);
3439 assert_eq!(fs::canonicalize(&linkdir.join("link")).unwrap(), file);
3443 fn realpath_works_tricky() {
3444 let tmpdir = tmpdir();
3445 if !got_symlink_permission(&tmpdir) {
3449 let tmpdir = fs::canonicalize(tmpdir.path()).unwrap();
3450 let a = tmpdir.join("a");
3451 let b = a.join("b");
3452 let c = b.join("c");
3453 let d = a.join("d");
3454 let e = d.join("e");
3455 let f = a.join("f");
3457 fs::create_dir_all(&b).unwrap();
3458 fs::create_dir_all(&d).unwrap();
3459 File::create(&f).unwrap();
3460 if cfg!(not(windows)) {
3461 symlink_file("../d/e", &c).unwrap();
3462 symlink_file("../f", &e).unwrap();
3465 symlink_file(r"..\d\e", &c).unwrap();
3466 symlink_file(r"..\f", &e).unwrap();
3469 assert_eq!(fs::canonicalize(&c).unwrap(), f);
3470 assert_eq!(fs::canonicalize(&e).unwrap(), f);
3474 fn dir_entry_methods() {
3475 let tmpdir = tmpdir();
3477 fs::create_dir_all(&tmpdir.join("a")).unwrap();
3478 File::create(&tmpdir.join("b")).unwrap();
3480 for file in tmpdir.path().read_dir().unwrap().map(|f| f.unwrap()) {
3481 let fname = file.file_name();
3482 match fname.to_str() {
3484 assert!(file.file_type().unwrap().is_dir());
3485 assert!(file.metadata().unwrap().is_dir());
3488 assert!(file.file_type().unwrap().is_file());
3489 assert!(file.metadata().unwrap().is_file());
3491 f => panic!("unknown file name: {:?}", f),
3497 fn dir_entry_debug() {
3498 let tmpdir = tmpdir();
3499 File::create(&tmpdir.join("b")).unwrap();
3500 let mut read_dir = tmpdir.path().read_dir().unwrap();
3501 let dir_entry = read_dir.next().unwrap().unwrap();
3502 let actual = format!("{:?}", dir_entry);
3503 let expected = format!("DirEntry({:?})", dir_entry.0.path());
3504 assert_eq!(actual, expected);
3508 fn read_dir_not_found() {
3509 let res = fs::read_dir("/path/that/does/not/exist");
3510 assert_eq!(res.err().unwrap().kind(), ErrorKind::NotFound);
3514 fn create_dir_all_with_junctions() {
3515 let tmpdir = tmpdir();
3516 let target = tmpdir.join("target");
3518 let junction = tmpdir.join("junction");
3519 let b = junction.join("a/b");
3521 let link = tmpdir.join("link");
3522 let d = link.join("c/d");
3524 fs::create_dir(&target).unwrap();
3526 check!(symlink_junction(&target, &junction));
3527 check!(fs::create_dir_all(&b));
3528 // the junction itself is not a directory, but `is_dir()` on a Path
3530 assert!(junction.is_dir());
3531 assert!(b.exists());
3533 if !got_symlink_permission(&tmpdir) {
3536 check!(symlink_dir(&target, &link));
3537 check!(fs::create_dir_all(&d));
3538 assert!(link.is_dir());
3539 assert!(d.exists());
3543 fn metadata_access_times() {
3544 let tmpdir = tmpdir();
3546 let b = tmpdir.join("b");
3547 File::create(&b).unwrap();
3549 let a = check!(fs::metadata(&tmpdir.path()));
3550 let b = check!(fs::metadata(&b));
3552 assert_eq!(check!(a.accessed()), check!(a.accessed()));
3553 assert_eq!(check!(a.modified()), check!(a.modified()));
3554 assert_eq!(check!(b.accessed()), check!(b.modified()));
3556 if cfg!(target_os = "macos") || cfg!(target_os = "windows") {
3557 check!(a.created());
3558 check!(b.created());
3561 if cfg!(target_os = "linux") {
3562 // Not always available
3563 match (a.created(), b.created()) {
3564 (Ok(t1), Ok(t2)) => assert!(t1 <= t2),
3566 if e1.kind() == ErrorKind::Other && e2.kind() == ErrorKind::Other => {}
3568 "creation time must be always supported or not supported: {:?} {:?}",