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")]
13 use crate::ffi::OsString;
14 use crate::io::{self, SeekFrom, Seek, Read, Initializer, Write, IoSlice, IoSliceMut};
15 use crate::path::{Path, PathBuf};
16 use crate::sys::fs as fs_imp;
17 use crate::sys_common::{AsInnerMut, FromInner, AsInner, 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> {
589 inner: self.inner.duplicate()?
593 /// Changes the permissions on the underlying file.
595 /// # Platform-specific behavior
597 /// This function currently corresponds to the `fchmod` function on Unix and
598 /// the `SetFileInformationByHandle` function on Windows. Note that, this
599 /// [may change in the future][changes].
601 /// [changes]: ../io/index.html#platform-specific-behavior
605 /// This function will return an error if the user lacks permission change
606 /// attributes on the underlying file. It may also return an error in other
607 /// os-specific unspecified cases.
612 /// fn main() -> std::io::Result<()> {
613 /// use std::fs::File;
615 /// let file = File::open("foo.txt")?;
616 /// let mut perms = file.metadata()?.permissions();
617 /// perms.set_readonly(true);
618 /// file.set_permissions(perms)?;
623 /// Note that this method alters the permissions of the underlying file,
624 /// even though it takes `&self` rather than `&mut self`.
625 #[stable(feature = "set_permissions_atomic", since = "1.16.0")]
626 pub fn set_permissions(&self, perm: Permissions) -> io::Result<()> {
627 self.inner.set_permissions(perm.0)
631 impl AsInner<fs_imp::File> for File {
632 fn as_inner(&self) -> &fs_imp::File { &self.inner }
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<()> { self.inner.flush() }
679 #[stable(feature = "rust1", since = "1.0.0")]
681 fn seek(&mut self, pos: SeekFrom) -> io::Result<u64> {
685 #[stable(feature = "rust1", since = "1.0.0")]
686 impl Read for &File {
687 fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
691 fn read_vectored(&mut self, bufs: &mut [IoSliceMut<'_>]) -> io::Result<usize> {
692 self.inner.read_vectored(bufs)
696 unsafe fn initializer(&self) -> Initializer {
700 #[stable(feature = "rust1", since = "1.0.0")]
701 impl Write for &File {
702 fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
703 self.inner.write(buf)
706 fn write_vectored(&mut self, bufs: &[IoSlice<'_>]) -> io::Result<usize> {
707 self.inner.write_vectored(bufs)
710 fn flush(&mut self) -> io::Result<()> { self.inner.flush() }
712 #[stable(feature = "rust1", since = "1.0.0")]
713 impl Seek for &File {
714 fn seek(&mut self, pos: SeekFrom) -> io::Result<u64> {
720 /// Creates a blank new set of options ready for configuration.
722 /// All options are initially set to `false`.
727 /// use std::fs::OpenOptions;
729 /// let mut options = OpenOptions::new();
730 /// let file = options.read(true).open("foo.txt");
732 #[stable(feature = "rust1", since = "1.0.0")]
733 pub fn new() -> OpenOptions {
734 OpenOptions(fs_imp::OpenOptions::new())
737 /// Sets the option for read access.
739 /// This option, when true, will indicate that the file should be
740 /// `read`-able if opened.
745 /// use std::fs::OpenOptions;
747 /// let file = OpenOptions::new().read(true).open("foo.txt");
749 #[stable(feature = "rust1", since = "1.0.0")]
750 pub fn read(&mut self, read: bool) -> &mut OpenOptions {
751 self.0.read(read); self
754 /// Sets the option for write access.
756 /// This option, when true, will indicate that the file should be
757 /// `write`-able if opened.
759 /// If the file already exists, any write calls on it will overwrite its
760 /// contents, without truncating it.
765 /// use std::fs::OpenOptions;
767 /// let file = OpenOptions::new().write(true).open("foo.txt");
769 #[stable(feature = "rust1", since = "1.0.0")]
770 pub fn write(&mut self, write: bool) -> &mut OpenOptions {
771 self.0.write(write); self
774 /// Sets the option for the append mode.
776 /// This option, when true, means that writes will append to a file instead
777 /// of overwriting previous contents.
778 /// Note that setting `.write(true).append(true)` has the same effect as
779 /// setting only `.append(true)`.
781 /// For most filesystems, the operating system guarantees that all writes are
782 /// atomic: no writes get mangled because another process writes at the same
785 /// One maybe obvious note when using append-mode: make sure that all data
786 /// that belongs together is written to the file in one operation. This
787 /// can be done by concatenating strings before passing them to [`write()`],
788 /// or using a buffered writer (with a buffer of adequate size),
789 /// and calling [`flush()`] when the message is complete.
791 /// If a file is opened with both read and append access, beware that after
792 /// opening, and after every write, the position for reading may be set at the
793 /// end of the file. So, before writing, save the current position (using
794 /// [`seek`]`(`[`SeekFrom`]`::`[`Current`]`(0))`), and restore it before the next read.
798 /// This function doesn't create the file if it doesn't exist. Use the [`create`]
801 /// [`write()`]: ../../std/fs/struct.File.html#method.write
802 /// [`flush()`]: ../../std/fs/struct.File.html#method.flush
803 /// [`seek`]: ../../std/fs/struct.File.html#method.seek
804 /// [`SeekFrom`]: ../../std/io/enum.SeekFrom.html
805 /// [`Current`]: ../../std/io/enum.SeekFrom.html#variant.Current
806 /// [`create`]: #method.create
811 /// use std::fs::OpenOptions;
813 /// let file = OpenOptions::new().append(true).open("foo.txt");
815 #[stable(feature = "rust1", since = "1.0.0")]
816 pub fn append(&mut self, append: bool) -> &mut OpenOptions {
817 self.0.append(append); self
820 /// Sets the option for truncating a previous file.
822 /// If a file is successfully opened with this option set it will truncate
823 /// the file to 0 length if it already exists.
825 /// The file must be opened with write access for truncate to work.
830 /// use std::fs::OpenOptions;
832 /// let file = OpenOptions::new().write(true).truncate(true).open("foo.txt");
834 #[stable(feature = "rust1", since = "1.0.0")]
835 pub fn truncate(&mut self, truncate: bool) -> &mut OpenOptions {
836 self.0.truncate(truncate); self
839 /// Sets the option for creating a new file.
841 /// This option indicates whether a new file will be created if the file
842 /// does not yet already exist.
844 /// In order for the file to be created, [`write`] or [`append`] access must
847 /// [`write`]: #method.write
848 /// [`append`]: #method.append
853 /// use std::fs::OpenOptions;
855 /// let file = OpenOptions::new().write(true).create(true).open("foo.txt");
857 #[stable(feature = "rust1", since = "1.0.0")]
858 pub fn create(&mut self, create: bool) -> &mut OpenOptions {
859 self.0.create(create); self
862 /// Sets the option to always create a new file.
864 /// This option indicates whether a new file will be created.
865 /// No file is allowed to exist at the target location, also no (dangling)
868 /// This option is useful because it is atomic. Otherwise between checking
869 /// whether a file exists and creating a new one, the file may have been
870 /// created by another process (a TOCTOU race condition / attack).
872 /// If `.create_new(true)` is set, [`.create()`] and [`.truncate()`] are
875 /// The file must be opened with write or append access in order to create
878 /// [`.create()`]: #method.create
879 /// [`.truncate()`]: #method.truncate
884 /// use std::fs::OpenOptions;
886 /// let file = OpenOptions::new().write(true)
887 /// .create_new(true)
888 /// .open("foo.txt");
890 #[stable(feature = "expand_open_options2", since = "1.9.0")]
891 pub fn create_new(&mut self, create_new: bool) -> &mut OpenOptions {
892 self.0.create_new(create_new); self
895 /// Opens a file at `path` with the options specified by `self`.
899 /// This function will return an error under a number of different
900 /// circumstances. Some of these error conditions are listed here, together
901 /// with their [`ErrorKind`]. The mapping to [`ErrorKind`]s is not part of
902 /// the compatibility contract of the function, especially the `Other` kind
903 /// might change to more specific kinds in the future.
905 /// * [`NotFound`]: The specified file does not exist and neither `create`
906 /// or `create_new` is set.
907 /// * [`NotFound`]: One of the directory components of the file path does
909 /// * [`PermissionDenied`]: The user lacks permission to get the specified
910 /// access rights for the file.
911 /// * [`PermissionDenied`]: The user lacks permission to open one of the
912 /// directory components of the specified path.
913 /// * [`AlreadyExists`]: `create_new` was specified and the file already
915 /// * [`InvalidInput`]: Invalid combinations of open options (truncate
916 /// without write access, no access mode set, etc.).
917 /// * [`Other`]: One of the directory components of the specified file path
918 /// was not, in fact, a directory.
919 /// * [`Other`]: Filesystem-level errors: full disk, write permission
920 /// requested on a read-only file system, exceeded disk quota, too many
921 /// open files, too long filename, too many symbolic links in the
922 /// specified path (Unix-like systems only), etc.
927 /// use std::fs::OpenOptions;
929 /// let file = OpenOptions::new().open("foo.txt");
932 /// [`ErrorKind`]: ../io/enum.ErrorKind.html
933 /// [`AlreadyExists`]: ../io/enum.ErrorKind.html#variant.AlreadyExists
934 /// [`InvalidInput`]: ../io/enum.ErrorKind.html#variant.InvalidInput
935 /// [`NotFound`]: ../io/enum.ErrorKind.html#variant.NotFound
936 /// [`Other`]: ../io/enum.ErrorKind.html#variant.Other
937 /// [`PermissionDenied`]: ../io/enum.ErrorKind.html#variant.PermissionDenied
938 #[stable(feature = "rust1", since = "1.0.0")]
939 pub fn open<P: AsRef<Path>>(&self, path: P) -> io::Result<File> {
940 self._open(path.as_ref())
943 fn _open(&self, path: &Path) -> io::Result<File> {
944 fs_imp::File::open(path, &self.0).map(|inner| File { inner })
948 impl AsInner<fs_imp::OpenOptions> for OpenOptions {
949 fn as_inner(&self) -> &fs_imp::OpenOptions { &self.0 }
952 impl AsInnerMut<fs_imp::OpenOptions> for OpenOptions {
953 fn as_inner_mut(&mut self) -> &mut fs_imp::OpenOptions { &mut self.0 }
957 /// Returns the file type for this metadata.
962 /// fn main() -> std::io::Result<()> {
965 /// let metadata = fs::metadata("foo.txt")?;
967 /// println!("{:?}", metadata.file_type());
971 #[stable(feature = "file_type", since = "1.1.0")]
972 pub fn file_type(&self) -> FileType {
973 FileType(self.0.file_type())
976 /// Returns `true` if this metadata is for a directory. The
977 /// result is mutually exclusive to the result of
978 /// [`is_file`], and will be false for symlink metadata
979 /// obtained from [`symlink_metadata`].
981 /// [`is_file`]: struct.Metadata.html#method.is_file
982 /// [`symlink_metadata`]: fn.symlink_metadata.html
987 /// fn main() -> std::io::Result<()> {
990 /// let metadata = fs::metadata("foo.txt")?;
992 /// assert!(!metadata.is_dir());
996 #[stable(feature = "rust1", since = "1.0.0")]
997 pub fn is_dir(&self) -> bool { self.file_type().is_dir() }
999 /// Returns `true` if this metadata is for a regular file. The
1000 /// result is mutually exclusive to the result of
1001 /// [`is_dir`], and will be false for symlink metadata
1002 /// obtained from [`symlink_metadata`].
1004 /// [`is_dir`]: struct.Metadata.html#method.is_dir
1005 /// [`symlink_metadata`]: fn.symlink_metadata.html
1012 /// fn main() -> std::io::Result<()> {
1013 /// let metadata = fs::metadata("foo.txt")?;
1015 /// assert!(metadata.is_file());
1019 #[stable(feature = "rust1", since = "1.0.0")]
1020 pub fn is_file(&self) -> bool { self.file_type().is_file() }
1022 /// Returns the size of the file, in bytes, this metadata is for.
1029 /// fn main() -> std::io::Result<()> {
1030 /// let metadata = fs::metadata("foo.txt")?;
1032 /// assert_eq!(0, metadata.len());
1036 #[stable(feature = "rust1", since = "1.0.0")]
1037 pub fn len(&self) -> u64 { self.0.size() }
1039 /// Returns the permissions of the file this metadata is for.
1046 /// fn main() -> std::io::Result<()> {
1047 /// let metadata = fs::metadata("foo.txt")?;
1049 /// assert!(!metadata.permissions().readonly());
1053 #[stable(feature = "rust1", since = "1.0.0")]
1054 pub fn permissions(&self) -> Permissions {
1055 Permissions(self.0.perm())
1058 /// Returns the last modification time listed in this metadata.
1060 /// The returned value corresponds to the `mtime` field of `stat` on Unix
1061 /// platforms and the `ftLastWriteTime` field on Windows platforms.
1065 /// This field may not be available on all platforms, and will return an
1066 /// `Err` on platforms where it is not available.
1073 /// fn main() -> std::io::Result<()> {
1074 /// let metadata = fs::metadata("foo.txt")?;
1076 /// if let Ok(time) = metadata.modified() {
1077 /// println!("{:?}", time);
1079 /// println!("Not supported on this platform");
1084 #[stable(feature = "fs_time", since = "1.10.0")]
1085 pub fn modified(&self) -> io::Result<SystemTime> {
1086 self.0.modified().map(FromInner::from_inner)
1089 /// Returns the last access time of this metadata.
1091 /// The returned value corresponds to the `atime` field of `stat` on Unix
1092 /// platforms and the `ftLastAccessTime` field on Windows platforms.
1094 /// Note that not all platforms will keep this field update in a file's
1095 /// metadata, for example Windows has an option to disable updating this
1096 /// time when files are accessed and Linux similarly has `noatime`.
1100 /// This field may not be available on all platforms, and will return an
1101 /// `Err` on platforms where it is not available.
1108 /// fn main() -> std::io::Result<()> {
1109 /// let metadata = fs::metadata("foo.txt")?;
1111 /// if let Ok(time) = metadata.accessed() {
1112 /// println!("{:?}", time);
1114 /// println!("Not supported on this platform");
1119 #[stable(feature = "fs_time", since = "1.10.0")]
1120 pub fn accessed(&self) -> io::Result<SystemTime> {
1121 self.0.accessed().map(FromInner::from_inner)
1124 /// Returns the creation time listed in this metadata.
1126 /// The returned value corresponds to the `btime` field of `statx` on
1127 /// Linux kernel starting from to 4.11, the `birthtime` field of `stat` on other
1128 /// Unix platforms, and the `ftCreationTime` field on Windows platforms.
1132 /// This field may not be available on all platforms, and will return an
1133 /// `Err` on platforms or filesystems where it is not available.
1140 /// fn main() -> std::io::Result<()> {
1141 /// let metadata = fs::metadata("foo.txt")?;
1143 /// if let Ok(time) = metadata.created() {
1144 /// println!("{:?}", time);
1146 /// println!("Not supported on this platform or filesystem");
1151 #[stable(feature = "fs_time", since = "1.10.0")]
1152 pub fn created(&self) -> io::Result<SystemTime> {
1153 self.0.created().map(FromInner::from_inner)
1157 #[stable(feature = "std_debug", since = "1.16.0")]
1158 impl fmt::Debug for Metadata {
1159 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1160 f.debug_struct("Metadata")
1161 .field("file_type", &self.file_type())
1162 .field("is_dir", &self.is_dir())
1163 .field("is_file", &self.is_file())
1164 .field("permissions", &self.permissions())
1165 .field("modified", &self.modified())
1166 .field("accessed", &self.accessed())
1167 .field("created", &self.created())
1172 impl AsInner<fs_imp::FileAttr> for Metadata {
1173 fn as_inner(&self) -> &fs_imp::FileAttr { &self.0 }
1176 impl FromInner<fs_imp::FileAttr> for Metadata {
1177 fn from_inner(attr: fs_imp::FileAttr) -> Metadata { Metadata(attr) }
1181 /// Returns `true` if these permissions describe a readonly (unwritable) file.
1186 /// use std::fs::File;
1188 /// fn main() -> std::io::Result<()> {
1189 /// let mut f = File::create("foo.txt")?;
1190 /// let metadata = f.metadata()?;
1192 /// assert_eq!(false, metadata.permissions().readonly());
1196 #[stable(feature = "rust1", since = "1.0.0")]
1197 pub fn readonly(&self) -> bool { self.0.readonly() }
1199 /// Modifies the readonly flag for this set of permissions. If the
1200 /// `readonly` argument is `true`, using the resulting `Permission` will
1201 /// update file permissions to forbid writing. Conversely, if it's `false`,
1202 /// using the resulting `Permission` will update file permissions to allow
1205 /// This operation does **not** modify the filesystem. To modify the
1206 /// filesystem use the [`fs::set_permissions`] function.
1208 /// [`fs::set_permissions`]: fn.set_permissions.html
1213 /// use std::fs::File;
1215 /// fn main() -> std::io::Result<()> {
1216 /// let f = File::create("foo.txt")?;
1217 /// let metadata = f.metadata()?;
1218 /// let mut permissions = metadata.permissions();
1220 /// permissions.set_readonly(true);
1222 /// // filesystem doesn't change
1223 /// assert_eq!(false, metadata.permissions().readonly());
1225 /// // just this particular `permissions`.
1226 /// assert_eq!(true, permissions.readonly());
1230 #[stable(feature = "rust1", since = "1.0.0")]
1231 pub fn set_readonly(&mut self, readonly: bool) {
1232 self.0.set_readonly(readonly)
1237 /// Tests whether this file type represents a directory. The
1238 /// result is mutually exclusive to the results of
1239 /// [`is_file`] and [`is_symlink`]; only zero or one of these
1242 /// [`is_file`]: struct.FileType.html#method.is_file
1243 /// [`is_symlink`]: struct.FileType.html#method.is_symlink
1248 /// fn main() -> std::io::Result<()> {
1251 /// let metadata = fs::metadata("foo.txt")?;
1252 /// let file_type = metadata.file_type();
1254 /// assert_eq!(file_type.is_dir(), false);
1258 #[stable(feature = "file_type", since = "1.1.0")]
1259 pub fn is_dir(&self) -> bool { self.0.is_dir() }
1261 /// Tests whether this file type represents a regular file.
1262 /// The result is mutually exclusive to the results of
1263 /// [`is_dir`] and [`is_symlink`]; only zero or one of these
1266 /// [`is_dir`]: struct.FileType.html#method.is_dir
1267 /// [`is_symlink`]: struct.FileType.html#method.is_symlink
1272 /// fn main() -> std::io::Result<()> {
1275 /// let metadata = fs::metadata("foo.txt")?;
1276 /// let file_type = metadata.file_type();
1278 /// assert_eq!(file_type.is_file(), true);
1282 #[stable(feature = "file_type", since = "1.1.0")]
1283 pub fn is_file(&self) -> bool { self.0.is_file() }
1285 /// Tests whether this file type represents a symbolic link.
1286 /// The result is mutually exclusive to the results of
1287 /// [`is_dir`] and [`is_file`]; only zero or one of these
1290 /// The underlying [`Metadata`] struct needs to be retrieved
1291 /// with the [`fs::symlink_metadata`] function and not the
1292 /// [`fs::metadata`] function. The [`fs::metadata`] function
1293 /// follows symbolic links, so [`is_symlink`] would always
1294 /// return `false` for the target file.
1296 /// [`Metadata`]: struct.Metadata.html
1297 /// [`fs::metadata`]: fn.metadata.html
1298 /// [`fs::symlink_metadata`]: fn.symlink_metadata.html
1299 /// [`is_dir`]: struct.FileType.html#method.is_dir
1300 /// [`is_file`]: struct.FileType.html#method.is_file
1301 /// [`is_symlink`]: struct.FileType.html#method.is_symlink
1308 /// fn main() -> std::io::Result<()> {
1309 /// let metadata = fs::symlink_metadata("foo.txt")?;
1310 /// let file_type = metadata.file_type();
1312 /// assert_eq!(file_type.is_symlink(), false);
1316 #[stable(feature = "file_type", since = "1.1.0")]
1317 pub fn is_symlink(&self) -> bool { self.0.is_symlink() }
1320 impl AsInner<fs_imp::FileType> for FileType {
1321 fn as_inner(&self) -> &fs_imp::FileType { &self.0 }
1324 impl FromInner<fs_imp::FilePermissions> for Permissions {
1325 fn from_inner(f: fs_imp::FilePermissions) -> Permissions {
1330 impl AsInner<fs_imp::FilePermissions> for Permissions {
1331 fn as_inner(&self) -> &fs_imp::FilePermissions { &self.0 }
1334 #[stable(feature = "rust1", since = "1.0.0")]
1335 impl Iterator for ReadDir {
1336 type Item = io::Result<DirEntry>;
1338 fn next(&mut self) -> Option<io::Result<DirEntry>> {
1339 self.0.next().map(|entry| entry.map(DirEntry))
1344 /// Returns the full path to the file that this entry represents.
1346 /// The full path is created by joining the original path to `read_dir`
1347 /// with the filename of this entry.
1354 /// fn main() -> std::io::Result<()> {
1355 /// for entry in fs::read_dir(".")? {
1356 /// let dir = entry?;
1357 /// println!("{:?}", dir.path());
1363 /// This prints output like:
1366 /// "./whatever.txt"
1368 /// "./hello_world.rs"
1371 /// The exact text, of course, depends on what files you have in `.`.
1372 #[stable(feature = "rust1", since = "1.0.0")]
1373 pub fn path(&self) -> PathBuf { self.0.path() }
1375 /// Returns the metadata for the file that this entry points at.
1377 /// This function will not traverse symlinks if this entry points at a
1380 /// # Platform-specific behavior
1382 /// On Windows this function is cheap to call (no extra system calls
1383 /// needed), but on Unix platforms this function is the equivalent of
1384 /// calling `symlink_metadata` on the path.
1391 /// if let Ok(entries) = fs::read_dir(".") {
1392 /// for entry in entries {
1393 /// if let Ok(entry) = entry {
1394 /// // Here, `entry` is a `DirEntry`.
1395 /// if let Ok(metadata) = entry.metadata() {
1396 /// // Now let's show our entry's permissions!
1397 /// println!("{:?}: {:?}", entry.path(), metadata.permissions());
1399 /// println!("Couldn't get metadata for {:?}", entry.path());
1405 #[stable(feature = "dir_entry_ext", since = "1.1.0")]
1406 pub fn metadata(&self) -> io::Result<Metadata> {
1407 self.0.metadata().map(Metadata)
1410 /// Returns the file type for the file that this entry points at.
1412 /// This function will not traverse symlinks if this entry points at a
1415 /// # Platform-specific behavior
1417 /// On Windows and most Unix platforms this function is free (no extra
1418 /// system calls needed), but some Unix platforms may require the equivalent
1419 /// call to `symlink_metadata` to learn about the target file type.
1426 /// if let Ok(entries) = fs::read_dir(".") {
1427 /// for entry in entries {
1428 /// if let Ok(entry) = entry {
1429 /// // Here, `entry` is a `DirEntry`.
1430 /// if let Ok(file_type) = entry.file_type() {
1431 /// // Now let's show our entry's file type!
1432 /// println!("{:?}: {:?}", entry.path(), file_type);
1434 /// println!("Couldn't get file type for {:?}", entry.path());
1440 #[stable(feature = "dir_entry_ext", since = "1.1.0")]
1441 pub fn file_type(&self) -> io::Result<FileType> {
1442 self.0.file_type().map(FileType)
1445 /// Returns the bare file name of this directory entry without any other
1446 /// leading path component.
1453 /// if let Ok(entries) = fs::read_dir(".") {
1454 /// for entry in entries {
1455 /// if let Ok(entry) = entry {
1456 /// // Here, `entry` is a `DirEntry`.
1457 /// println!("{:?}", entry.file_name());
1462 #[stable(feature = "dir_entry_ext", since = "1.1.0")]
1463 pub fn file_name(&self) -> OsString {
1468 #[stable(feature = "dir_entry_debug", since = "1.13.0")]
1469 impl fmt::Debug for DirEntry {
1470 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1471 f.debug_tuple("DirEntry")
1472 .field(&self.path())
1477 impl AsInner<fs_imp::DirEntry> for DirEntry {
1478 fn as_inner(&self) -> &fs_imp::DirEntry { &self.0 }
1481 /// Removes a file from the filesystem.
1483 /// Note that there is no
1484 /// guarantee that the file is immediately deleted (e.g., depending on
1485 /// platform, other open file descriptors may prevent immediate removal).
1487 /// # Platform-specific behavior
1489 /// This function currently corresponds to the `unlink` function on Unix
1490 /// and the `DeleteFile` function on Windows.
1491 /// Note that, this [may change in the future][changes].
1493 /// [changes]: ../io/index.html#platform-specific-behavior
1497 /// This function will return an error in the following situations, but is not
1498 /// limited to just these cases:
1500 /// * `path` points to a directory.
1501 /// * The user lacks permissions to remove the file.
1508 /// fn main() -> std::io::Result<()> {
1509 /// fs::remove_file("a.txt")?;
1513 #[stable(feature = "rust1", since = "1.0.0")]
1514 pub fn remove_file<P: AsRef<Path>>(path: P) -> io::Result<()> {
1515 fs_imp::unlink(path.as_ref())
1518 /// Given a path, query the file system to get information about a file,
1521 /// This function will traverse symbolic links to query information about the
1522 /// destination file.
1524 /// # Platform-specific behavior
1526 /// This function currently corresponds to the `stat` function on Unix
1527 /// and the `GetFileAttributesEx` function on Windows.
1528 /// Note that, this [may change in the future][changes].
1530 /// [changes]: ../io/index.html#platform-specific-behavior
1534 /// This function will return an error in the following situations, but is not
1535 /// limited to just these cases:
1537 /// * The user lacks permissions to perform `metadata` call on `path`.
1538 /// * `path` does not exist.
1545 /// fn main() -> std::io::Result<()> {
1546 /// let attr = fs::metadata("/some/file/path.txt")?;
1547 /// // inspect attr ...
1551 #[stable(feature = "rust1", since = "1.0.0")]
1552 pub fn metadata<P: AsRef<Path>>(path: P) -> io::Result<Metadata> {
1553 fs_imp::stat(path.as_ref()).map(Metadata)
1556 /// Query the metadata about a file without following symlinks.
1558 /// # Platform-specific behavior
1560 /// This function currently corresponds to the `lstat` function on Unix
1561 /// and the `GetFileAttributesEx` function on Windows.
1562 /// Note that, this [may change in the future][changes].
1564 /// [changes]: ../io/index.html#platform-specific-behavior
1568 /// This function will return an error in the following situations, but is not
1569 /// limited to just these cases:
1571 /// * The user lacks permissions to perform `metadata` call on `path`.
1572 /// * `path` does not exist.
1579 /// fn main() -> std::io::Result<()> {
1580 /// let attr = fs::symlink_metadata("/some/file/path.txt")?;
1581 /// // inspect attr ...
1585 #[stable(feature = "symlink_metadata", since = "1.1.0")]
1586 pub fn symlink_metadata<P: AsRef<Path>>(path: P) -> io::Result<Metadata> {
1587 fs_imp::lstat(path.as_ref()).map(Metadata)
1590 /// Rename a file or directory to a new name, replacing the original file if
1591 /// `to` already exists.
1593 /// This will not work if the new name is on a different mount point.
1595 /// # Platform-specific behavior
1597 /// This function currently corresponds to the `rename` function on Unix
1598 /// and the `MoveFileEx` function with the `MOVEFILE_REPLACE_EXISTING` flag on Windows.
1600 /// Because of this, the behavior when both `from` and `to` exist differs. On
1601 /// Unix, if `from` is a directory, `to` must also be an (empty) directory. If
1602 /// `from` is not a directory, `to` must also be not a directory. In contrast,
1603 /// on Windows, `from` can be anything, but `to` must *not* be a directory.
1605 /// Note that, this [may change in the future][changes].
1607 /// [changes]: ../io/index.html#platform-specific-behavior
1611 /// This function will return an error in the following situations, but is not
1612 /// limited to just these cases:
1614 /// * `from` does not exist.
1615 /// * The user lacks permissions to view contents.
1616 /// * `from` and `to` are on separate filesystems.
1623 /// fn main() -> std::io::Result<()> {
1624 /// fs::rename("a.txt", "b.txt")?; // Rename a.txt to b.txt
1628 #[stable(feature = "rust1", since = "1.0.0")]
1629 pub fn rename<P: AsRef<Path>, Q: AsRef<Path>>(from: P, to: Q) -> io::Result<()> {
1630 fs_imp::rename(from.as_ref(), to.as_ref())
1633 /// Copies the contents of one file to another. This function will also
1634 /// copy the permission bits of the original file to the destination file.
1636 /// This function will **overwrite** the contents of `to`.
1638 /// Note that if `from` and `to` both point to the same file, then the file
1639 /// will likely get truncated by this operation.
1641 /// On success, the total number of bytes copied is returned and it is equal to
1642 /// the length of the `to` file as reported by `metadata`.
1644 /// If you’re wanting to copy the contents of one file to another and you’re
1645 /// working with [`File`]s, see the [`io::copy`] function.
1647 /// [`io::copy`]: ../io/fn.copy.html
1648 /// [`File`]: ./struct.File.html
1650 /// # Platform-specific behavior
1652 /// This function currently corresponds to the `open` function in Unix
1653 /// with `O_RDONLY` for `from` and `O_WRONLY`, `O_CREAT`, and `O_TRUNC` for `to`.
1654 /// `O_CLOEXEC` is set for returned file descriptors.
1655 /// On Windows, this function currently corresponds to `CopyFileEx`. Alternate
1656 /// NTFS streams are copied but only the size of the main stream is returned by
1657 /// this function. On MacOS, this function corresponds to `fclonefileat` and
1659 /// Note that, this [may change in the future][changes].
1661 /// [changes]: ../io/index.html#platform-specific-behavior
1665 /// This function will return an error in the following situations, but is not
1666 /// limited to just these cases:
1668 /// * The `from` path is not a file.
1669 /// * The `from` file does not exist.
1670 /// * The current process does not have the permission rights to access
1671 /// `from` or write `to`.
1678 /// fn main() -> std::io::Result<()> {
1679 /// fs::copy("foo.txt", "bar.txt")?; // Copy foo.txt to bar.txt
1683 #[stable(feature = "rust1", since = "1.0.0")]
1684 pub fn copy<P: AsRef<Path>, Q: AsRef<Path>>(from: P, to: Q) -> io::Result<u64> {
1685 fs_imp::copy(from.as_ref(), to.as_ref())
1688 /// Creates a new hard link on the filesystem.
1690 /// The `dst` path will be a link pointing to the `src` path. Note that systems
1691 /// often require these two paths to both be located on the same filesystem.
1693 /// # Platform-specific behavior
1695 /// This function currently corresponds to the `link` function on Unix
1696 /// and the `CreateHardLink` function on Windows.
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 `src` path is not a file or doesn't exist.
1713 /// fn main() -> std::io::Result<()> {
1714 /// fs::hard_link("a.txt", "b.txt")?; // Hard link a.txt to b.txt
1718 #[stable(feature = "rust1", since = "1.0.0")]
1719 pub fn hard_link<P: AsRef<Path>, Q: AsRef<Path>>(src: P, dst: Q) -> io::Result<()> {
1720 fs_imp::link(src.as_ref(), dst.as_ref())
1723 /// Creates a new symbolic link on the filesystem.
1725 /// The `dst` path will be a symbolic link pointing to the `src` path.
1726 /// On Windows, this will be a file symlink, not a directory symlink;
1727 /// for this reason, the platform-specific [`std::os::unix::fs::symlink`]
1728 /// and [`std::os::windows::fs::symlink_file`] or [`symlink_dir`] should be
1729 /// used instead to make the intent explicit.
1731 /// [`std::os::unix::fs::symlink`]: ../os/unix/fs/fn.symlink.html
1732 /// [`std::os::windows::fs::symlink_file`]: ../os/windows/fs/fn.symlink_file.html
1733 /// [`symlink_dir`]: ../os/windows/fs/fn.symlink_dir.html
1741 /// fn main() -> std::io::Result<()> {
1742 /// fs::soft_link("a.txt", "b.txt")?;
1746 #[stable(feature = "rust1", since = "1.0.0")]
1747 #[rustc_deprecated(since = "1.1.0",
1748 reason = "replaced with std::os::unix::fs::symlink and \
1749 std::os::windows::fs::{symlink_file, symlink_dir}")]
1750 pub fn soft_link<P: AsRef<Path>, Q: AsRef<Path>>(src: P, dst: Q) -> io::Result<()> {
1751 fs_imp::symlink(src.as_ref(), dst.as_ref())
1754 /// Reads a symbolic link, returning the file that the link points to.
1756 /// # Platform-specific behavior
1758 /// This function currently corresponds to the `readlink` function on Unix
1759 /// and the `CreateFile` function with `FILE_FLAG_OPEN_REPARSE_POINT` and
1760 /// `FILE_FLAG_BACKUP_SEMANTICS` flags on Windows.
1761 /// Note that, this [may change in the future][changes].
1763 /// [changes]: ../io/index.html#platform-specific-behavior
1767 /// This function will return an error in the following situations, but is not
1768 /// limited to just these cases:
1770 /// * `path` is not a symbolic link.
1771 /// * `path` does not exist.
1778 /// fn main() -> std::io::Result<()> {
1779 /// let path = fs::read_link("a.txt")?;
1783 #[stable(feature = "rust1", since = "1.0.0")]
1784 pub fn read_link<P: AsRef<Path>>(path: P) -> io::Result<PathBuf> {
1785 fs_imp::readlink(path.as_ref())
1788 /// Returns the canonical, absolute form of a path with all intermediate
1789 /// components normalized and symbolic links resolved.
1791 /// # Platform-specific behavior
1793 /// This function currently corresponds to the `realpath` function on Unix
1794 /// and the `CreateFile` and `GetFinalPathNameByHandle` functions on Windows.
1795 /// Note that, this [may change in the future][changes].
1797 /// On Windows, this converts the path to use [extended length path][path]
1798 /// syntax, which allows your program to use longer path names, but means you
1799 /// can only join backslash-delimited paths to it, and it may be incompatible
1800 /// with other applications (if passed to the application on the command-line,
1801 /// or written to a file another application may read).
1803 /// [changes]: ../io/index.html#platform-specific-behavior
1804 /// [path]: https://msdn.microsoft.com/en-us/library/windows/desktop/aa365247(v=vs.85).aspx#maxpath
1808 /// This function will return an error in the following situations, but is not
1809 /// limited to just these cases:
1811 /// * `path` does not exist.
1812 /// * A non-final component in path is not a directory.
1819 /// fn main() -> std::io::Result<()> {
1820 /// let path = fs::canonicalize("../a/../foo.txt")?;
1824 #[stable(feature = "fs_canonicalize", since = "1.5.0")]
1825 pub fn canonicalize<P: AsRef<Path>>(path: P) -> io::Result<PathBuf> {
1826 fs_imp::canonicalize(path.as_ref())
1829 /// Creates a new, empty directory at the provided path
1831 /// # Platform-specific behavior
1833 /// This function currently corresponds to the `mkdir` function on Unix
1834 /// and the `CreateDirectory` function on Windows.
1835 /// Note that, this [may change in the future][changes].
1837 /// [changes]: ../io/index.html#platform-specific-behavior
1839 /// **NOTE**: If a parent of the given path doesn't exist, this function will
1840 /// return an error. To create a directory and all its missing parents at the
1841 /// same time, use the [`create_dir_all`] function.
1845 /// This function will return an error in the following situations, but is not
1846 /// limited to just these cases:
1848 /// * User lacks permissions to create directory at `path`.
1849 /// * A parent of the given path doesn't exist. (To create a directory and all
1850 /// its missing parents at the same time, use the [`create_dir_all`]
1852 /// * `path` already exists.
1854 /// [`create_dir_all`]: fn.create_dir_all.html
1861 /// fn main() -> std::io::Result<()> {
1862 /// fs::create_dir("/some/dir")?;
1866 #[stable(feature = "rust1", since = "1.0.0")]
1867 pub fn create_dir<P: AsRef<Path>>(path: P) -> io::Result<()> {
1868 DirBuilder::new().create(path.as_ref())
1871 /// Recursively create a directory and all of its parent components if they
1874 /// # Platform-specific behavior
1876 /// This function currently corresponds to the `mkdir` function on Unix
1877 /// and the `CreateDirectory` function on Windows.
1878 /// Note that, this [may change in the future][changes].
1880 /// [changes]: ../io/index.html#platform-specific-behavior
1884 /// This function will return an error in the following situations, but is not
1885 /// limited to just these cases:
1887 /// * If any directory in the path specified by `path`
1888 /// does not already exist and it could not be created otherwise. The specific
1889 /// error conditions for when a directory is being created (after it is
1890 /// determined to not exist) are outlined by [`fs::create_dir`].
1892 /// Notable exception is made for situations where any of the directories
1893 /// specified in the `path` could not be created as it was being created concurrently.
1894 /// Such cases are considered to be successful. That is, calling `create_dir_all`
1895 /// concurrently from multiple threads or processes is guaranteed not to fail
1896 /// due to a race condition with itself.
1898 /// [`fs::create_dir`]: fn.create_dir.html
1905 /// fn main() -> std::io::Result<()> {
1906 /// fs::create_dir_all("/some/dir")?;
1910 #[stable(feature = "rust1", since = "1.0.0")]
1911 pub fn create_dir_all<P: AsRef<Path>>(path: P) -> io::Result<()> {
1912 DirBuilder::new().recursive(true).create(path.as_ref())
1915 /// Removes an existing, empty directory.
1917 /// # Platform-specific behavior
1919 /// This function currently corresponds to the `rmdir` function on Unix
1920 /// and the `RemoveDirectory` function on Windows.
1921 /// Note that, this [may change in the future][changes].
1923 /// [changes]: ../io/index.html#platform-specific-behavior
1927 /// This function will return an error in the following situations, but is not
1928 /// limited to just these cases:
1930 /// * The user lacks permissions to remove the directory at the provided `path`.
1931 /// * The directory isn't empty.
1938 /// fn main() -> std::io::Result<()> {
1939 /// fs::remove_dir("/some/dir")?;
1943 #[stable(feature = "rust1", since = "1.0.0")]
1944 pub fn remove_dir<P: AsRef<Path>>(path: P) -> io::Result<()> {
1945 fs_imp::rmdir(path.as_ref())
1948 /// Removes a directory at this path, after removing all its contents. Use
1951 /// This function does **not** follow symbolic links and it will simply remove the
1952 /// symbolic link itself.
1954 /// # Platform-specific behavior
1956 /// This function currently corresponds to `opendir`, `lstat`, `rm` and `rmdir` functions on Unix
1957 /// and the `FindFirstFile`, `GetFileAttributesEx`, `DeleteFile`, and `RemoveDirectory` functions
1959 /// Note that, this [may change in the future][changes].
1961 /// [changes]: ../io/index.html#platform-specific-behavior
1965 /// See [`fs::remove_file`] and [`fs::remove_dir`].
1967 /// [`fs::remove_file`]: fn.remove_file.html
1968 /// [`fs::remove_dir`]: fn.remove_dir.html
1975 /// fn main() -> std::io::Result<()> {
1976 /// fs::remove_dir_all("/some/dir")?;
1980 #[stable(feature = "rust1", since = "1.0.0")]
1981 pub fn remove_dir_all<P: AsRef<Path>>(path: P) -> io::Result<()> {
1982 fs_imp::remove_dir_all(path.as_ref())
1985 /// Returns an iterator over the entries within a directory.
1987 /// The iterator will yield instances of [`io::Result`]`<`[`DirEntry`]`>`.
1988 /// New errors may be encountered after an iterator is initially constructed.
1990 /// [`io::Result`]: ../io/type.Result.html
1991 /// [`DirEntry`]: struct.DirEntry.html
1993 /// # Platform-specific behavior
1995 /// This function currently corresponds to the `opendir` function on Unix
1996 /// and the `FindFirstFile` function on Windows. Advancing the iterator
1997 /// currently corresponds to `readdir` on Unix and `FindNextFile` on Windows.
1998 /// Note that, this [may change in the future][changes].
2000 /// [changes]: ../io/index.html#platform-specific-behavior
2002 /// The order in which this iterator returns entries is platform and filesystem
2007 /// This function will return an error in the following situations, but is not
2008 /// limited to just these cases:
2010 /// * The provided `path` doesn't exist.
2011 /// * The process lacks permissions to view the contents.
2012 /// * The `path` points at a non-directory file.
2018 /// use std::fs::{self, DirEntry};
2019 /// use std::path::Path;
2021 /// // one possible implementation of walking a directory only visiting files
2022 /// fn visit_dirs(dir: &Path, cb: &dyn Fn(&DirEntry)) -> io::Result<()> {
2023 /// if dir.is_dir() {
2024 /// for entry in fs::read_dir(dir)? {
2025 /// let entry = entry?;
2026 /// let path = entry.path();
2027 /// if path.is_dir() {
2028 /// visit_dirs(&path, cb)?;
2039 /// use std::{fs, io};
2041 /// fn main() -> io::Result<()> {
2042 /// let mut entries = fs::read_dir(".")?
2043 /// .map(|res| res.map(|e| e.path()))
2044 /// .collect::<Result<Vec<_>, io::Error>>()?;
2046 /// // The order in which `read_dir` returns entries is not guaranteed. If reproducible
2047 /// // ordering is required the entries should be explicitly sorted.
2051 /// // The entries have now been sorted by their path.
2056 #[stable(feature = "rust1", since = "1.0.0")]
2057 pub fn read_dir<P: AsRef<Path>>(path: P) -> io::Result<ReadDir> {
2058 fs_imp::readdir(path.as_ref()).map(ReadDir)
2061 /// Changes the permissions found on a file or a directory.
2063 /// # Platform-specific behavior
2065 /// This function currently corresponds to the `chmod` function on Unix
2066 /// and the `SetFileAttributes` function on Windows.
2067 /// Note that, this [may change in the future][changes].
2069 /// [changes]: ../io/index.html#platform-specific-behavior
2073 /// This function will return an error in the following situations, but is not
2074 /// limited to just these cases:
2076 /// * `path` does not exist.
2077 /// * The user lacks the permission to change attributes of the file.
2084 /// fn main() -> std::io::Result<()> {
2085 /// let mut perms = fs::metadata("foo.txt")?.permissions();
2086 /// perms.set_readonly(true);
2087 /// fs::set_permissions("foo.txt", perms)?;
2091 #[stable(feature = "set_permissions", since = "1.1.0")]
2092 pub fn set_permissions<P: AsRef<Path>>(path: P, perm: Permissions)
2094 fs_imp::set_perm(path.as_ref(), perm.0)
2098 /// Creates a new set of options with default mode/security settings for all
2099 /// platforms and also non-recursive.
2104 /// use std::fs::DirBuilder;
2106 /// let builder = DirBuilder::new();
2108 #[stable(feature = "dir_builder", since = "1.6.0")]
2109 pub fn new() -> DirBuilder {
2111 inner: fs_imp::DirBuilder::new(),
2116 /// Indicates that directories should be created recursively, creating all
2117 /// parent directories. Parents that do not exist are created with the same
2118 /// security and permissions settings.
2120 /// This option defaults to `false`.
2125 /// use std::fs::DirBuilder;
2127 /// let mut builder = DirBuilder::new();
2128 /// builder.recursive(true);
2130 #[stable(feature = "dir_builder", since = "1.6.0")]
2131 pub fn recursive(&mut self, recursive: bool) -> &mut Self {
2132 self.recursive = recursive;
2136 /// Creates the specified directory with the options configured in this
2139 /// It is considered an error if the directory already exists unless
2140 /// recursive mode is enabled.
2145 /// use std::fs::{self, DirBuilder};
2147 /// let path = "/tmp/foo/bar/baz";
2148 /// DirBuilder::new()
2149 /// .recursive(true)
2150 /// .create(path).unwrap();
2152 /// assert!(fs::metadata(path).unwrap().is_dir());
2154 #[stable(feature = "dir_builder", since = "1.6.0")]
2155 pub fn create<P: AsRef<Path>>(&self, path: P) -> io::Result<()> {
2156 self._create(path.as_ref())
2159 fn _create(&self, path: &Path) -> io::Result<()> {
2161 self.create_dir_all(path)
2163 self.inner.mkdir(path)
2167 fn create_dir_all(&self, path: &Path) -> io::Result<()> {
2168 if path == Path::new("") {
2172 match self.inner.mkdir(path) {
2173 Ok(()) => return Ok(()),
2174 Err(ref e) if e.kind() == io::ErrorKind::NotFound => {}
2175 Err(_) if path.is_dir() => return Ok(()),
2176 Err(e) => return Err(e),
2178 match path.parent() {
2179 Some(p) => self.create_dir_all(p)?,
2180 None => return Err(io::Error::new(io::ErrorKind::Other, "failed to create whole tree")),
2182 match self.inner.mkdir(path) {
2184 Err(_) if path.is_dir() => Ok(()),
2190 impl AsInnerMut<fs_imp::DirBuilder> for DirBuilder {
2191 fn as_inner_mut(&mut self) -> &mut fs_imp::DirBuilder {
2196 #[cfg(all(test, not(any(target_os = "cloudabi", target_os = "emscripten", target_env = "sgx"))))]
2198 use crate::io::prelude::*;
2200 use crate::fs::{self, File, OpenOptions};
2201 use crate::io::{ErrorKind, SeekFrom};
2202 use crate::path::Path;
2204 use crate::sys_common::io::test::{TempDir, tmpdir};
2207 use rand::{rngs::StdRng, RngCore, SeedableRng};
2210 use crate::os::windows::fs::{symlink_dir, symlink_file};
2212 use crate::sys::fs::symlink_junction;
2214 use crate::os::unix::fs::symlink as symlink_dir;
2216 use crate::os::unix::fs::symlink as symlink_file;
2218 use crate::os::unix::fs::symlink as symlink_junction;
2220 macro_rules! check { ($e:expr) => (
2223 Err(e) => panic!("{} failed with: {}", stringify!($e), e),
2228 macro_rules! error { ($e:expr, $s:expr) => (
2230 Ok(_) => panic!("Unexpected success. Should've been: {:?}", $s),
2231 Err(ref err) => assert!(err.raw_os_error() == Some($s),
2232 format!("`{}` did not have a code of `{}`", err, $s))
2237 macro_rules! error { ($e:expr, $s:expr) => ( error_contains!($e, $s) ) }
2239 macro_rules! error_contains { ($e:expr, $s:expr) => (
2241 Ok(_) => panic!("Unexpected success. Should've been: {:?}", $s),
2242 Err(ref err) => assert!(err.to_string().contains($s),
2243 format!("`{}` did not contain `{}`", err, $s))
2247 // Several test fail on windows if the user does not have permission to
2248 // create symlinks (the `SeCreateSymbolicLinkPrivilege`). Instead of
2249 // disabling these test on Windows, use this function to test whether we
2250 // have permission, and return otherwise. This way, we still don't run these
2251 // tests most of the time, but at least we do if the user has the right
2253 pub fn got_symlink_permission(tmpdir: &TempDir) -> bool {
2254 if cfg!(unix) { return true }
2255 let link = tmpdir.join("some_hopefully_unique_link_name");
2257 match symlink_file(r"nonexisting_target", link) {
2259 // ERROR_PRIVILEGE_NOT_HELD = 1314
2260 Err(ref err) if err.raw_os_error() == Some(1314) => false,
2266 fn file_test_io_smoke_test() {
2267 let message = "it's alright. have a good time";
2268 let tmpdir = tmpdir();
2269 let filename = &tmpdir.join("file_rt_io_file_test.txt");
2271 let mut write_stream = check!(File::create(filename));
2272 check!(write_stream.write(message.as_bytes()));
2275 let mut read_stream = check!(File::open(filename));
2276 let mut read_buf = [0; 1028];
2277 let read_str = match check!(read_stream.read(&mut read_buf)) {
2278 0 => panic!("shouldn't happen"),
2279 n => str::from_utf8(&read_buf[..n]).unwrap().to_string()
2281 assert_eq!(read_str, message);
2283 check!(fs::remove_file(filename));
2287 fn invalid_path_raises() {
2288 let tmpdir = tmpdir();
2289 let filename = &tmpdir.join("file_that_does_not_exist.txt");
2290 let result = File::open(filename);
2293 error!(result, "No such file or directory");
2295 error!(result, 2); // ERROR_FILE_NOT_FOUND
2299 fn file_test_iounlinking_invalid_path_should_raise_condition() {
2300 let tmpdir = tmpdir();
2301 let filename = &tmpdir.join("file_another_file_that_does_not_exist.txt");
2303 let result = fs::remove_file(filename);
2306 error!(result, "No such file or directory");
2308 error!(result, 2); // ERROR_FILE_NOT_FOUND
2312 fn file_test_io_non_positional_read() {
2313 let message: &str = "ten-four";
2314 let mut read_mem = [0; 8];
2315 let tmpdir = tmpdir();
2316 let filename = &tmpdir.join("file_rt_io_file_test_positional.txt");
2318 let mut rw_stream = check!(File::create(filename));
2319 check!(rw_stream.write(message.as_bytes()));
2322 let mut read_stream = check!(File::open(filename));
2324 let read_buf = &mut read_mem[0..4];
2325 check!(read_stream.read(read_buf));
2328 let read_buf = &mut read_mem[4..8];
2329 check!(read_stream.read(read_buf));
2332 check!(fs::remove_file(filename));
2333 let read_str = str::from_utf8(&read_mem).unwrap();
2334 assert_eq!(read_str, message);
2338 fn file_test_io_seek_and_tell_smoke_test() {
2339 let message = "ten-four";
2340 let mut read_mem = [0; 4];
2341 let set_cursor = 4 as u64;
2342 let tell_pos_pre_read;
2343 let tell_pos_post_read;
2344 let tmpdir = tmpdir();
2345 let filename = &tmpdir.join("file_rt_io_file_test_seeking.txt");
2347 let mut rw_stream = check!(File::create(filename));
2348 check!(rw_stream.write(message.as_bytes()));
2351 let mut read_stream = check!(File::open(filename));
2352 check!(read_stream.seek(SeekFrom::Start(set_cursor)));
2353 tell_pos_pre_read = check!(read_stream.seek(SeekFrom::Current(0)));
2354 check!(read_stream.read(&mut read_mem));
2355 tell_pos_post_read = check!(read_stream.seek(SeekFrom::Current(0)));
2357 check!(fs::remove_file(filename));
2358 let read_str = str::from_utf8(&read_mem).unwrap();
2359 assert_eq!(read_str, &message[4..8]);
2360 assert_eq!(tell_pos_pre_read, set_cursor);
2361 assert_eq!(tell_pos_post_read, message.len() as u64);
2365 fn file_test_io_seek_and_write() {
2366 let initial_msg = "food-is-yummy";
2367 let overwrite_msg = "-the-bar!!";
2368 let final_msg = "foo-the-bar!!";
2370 let mut read_mem = [0; 13];
2371 let tmpdir = tmpdir();
2372 let filename = &tmpdir.join("file_rt_io_file_test_seek_and_write.txt");
2374 let mut rw_stream = check!(File::create(filename));
2375 check!(rw_stream.write(initial_msg.as_bytes()));
2376 check!(rw_stream.seek(SeekFrom::Start(seek_idx)));
2377 check!(rw_stream.write(overwrite_msg.as_bytes()));
2380 let mut read_stream = check!(File::open(filename));
2381 check!(read_stream.read(&mut read_mem));
2383 check!(fs::remove_file(filename));
2384 let read_str = str::from_utf8(&read_mem).unwrap();
2385 assert!(read_str == final_msg);
2389 fn file_test_io_seek_shakedown() {
2391 let initial_msg = "qwer-asdf-zxcv";
2392 let chunk_one: &str = "qwer";
2393 let chunk_two: &str = "asdf";
2394 let chunk_three: &str = "zxcv";
2395 let mut read_mem = [0; 4];
2396 let tmpdir = tmpdir();
2397 let filename = &tmpdir.join("file_rt_io_file_test_seek_shakedown.txt");
2399 let mut rw_stream = check!(File::create(filename));
2400 check!(rw_stream.write(initial_msg.as_bytes()));
2403 let mut read_stream = check!(File::open(filename));
2405 check!(read_stream.seek(SeekFrom::End(-4)));
2406 check!(read_stream.read(&mut read_mem));
2407 assert_eq!(str::from_utf8(&read_mem).unwrap(), chunk_three);
2409 check!(read_stream.seek(SeekFrom::Current(-9)));
2410 check!(read_stream.read(&mut read_mem));
2411 assert_eq!(str::from_utf8(&read_mem).unwrap(), chunk_two);
2413 check!(read_stream.seek(SeekFrom::Start(0)));
2414 check!(read_stream.read(&mut read_mem));
2415 assert_eq!(str::from_utf8(&read_mem).unwrap(), chunk_one);
2417 check!(fs::remove_file(filename));
2421 fn file_test_io_eof() {
2422 let tmpdir = tmpdir();
2423 let filename = tmpdir.join("file_rt_io_file_test_eof.txt");
2424 let mut buf = [0; 256];
2426 let oo = OpenOptions::new().create_new(true).write(true).read(true).clone();
2427 let mut rw = check!(oo.open(&filename));
2428 assert_eq!(check!(rw.read(&mut buf)), 0);
2429 assert_eq!(check!(rw.read(&mut buf)), 0);
2431 check!(fs::remove_file(&filename));
2436 fn file_test_io_read_write_at() {
2437 use crate::os::unix::fs::FileExt;
2439 let tmpdir = tmpdir();
2440 let filename = tmpdir.join("file_rt_io_file_test_read_write_at.txt");
2441 let mut buf = [0; 256];
2442 let write1 = "asdf";
2443 let write2 = "qwer-";
2444 let write3 = "-zxcv";
2445 let content = "qwer-asdf-zxcv";
2447 let oo = OpenOptions::new().create_new(true).write(true).read(true).clone();
2448 let mut rw = check!(oo.open(&filename));
2449 assert_eq!(check!(rw.write_at(write1.as_bytes(), 5)), write1.len());
2450 assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 0);
2451 assert_eq!(check!(rw.read_at(&mut buf, 5)), write1.len());
2452 assert_eq!(str::from_utf8(&buf[..write1.len()]), Ok(write1));
2453 assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 0);
2454 assert_eq!(check!(rw.read_at(&mut buf[..write2.len()], 0)), write2.len());
2455 assert_eq!(str::from_utf8(&buf[..write2.len()]), Ok("\0\0\0\0\0"));
2456 assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 0);
2457 assert_eq!(check!(rw.write(write2.as_bytes())), write2.len());
2458 assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 5);
2459 assert_eq!(check!(rw.read(&mut buf)), write1.len());
2460 assert_eq!(str::from_utf8(&buf[..write1.len()]), Ok(write1));
2461 assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 9);
2462 assert_eq!(check!(rw.read_at(&mut buf[..write2.len()], 0)), write2.len());
2463 assert_eq!(str::from_utf8(&buf[..write2.len()]), Ok(write2));
2464 assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 9);
2465 assert_eq!(check!(rw.write_at(write3.as_bytes(), 9)), write3.len());
2466 assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 9);
2469 let mut read = check!(File::open(&filename));
2470 assert_eq!(check!(read.read_at(&mut buf, 0)), content.len());
2471 assert_eq!(str::from_utf8(&buf[..content.len()]), Ok(content));
2472 assert_eq!(check!(read.seek(SeekFrom::Current(0))), 0);
2473 assert_eq!(check!(read.seek(SeekFrom::End(-5))), 9);
2474 assert_eq!(check!(read.read_at(&mut buf, 0)), content.len());
2475 assert_eq!(str::from_utf8(&buf[..content.len()]), Ok(content));
2476 assert_eq!(check!(read.seek(SeekFrom::Current(0))), 9);
2477 assert_eq!(check!(read.read(&mut buf)), write3.len());
2478 assert_eq!(str::from_utf8(&buf[..write3.len()]), Ok(write3));
2479 assert_eq!(check!(read.seek(SeekFrom::Current(0))), 14);
2480 assert_eq!(check!(read.read_at(&mut buf, 0)), content.len());
2481 assert_eq!(str::from_utf8(&buf[..content.len()]), Ok(content));
2482 assert_eq!(check!(read.seek(SeekFrom::Current(0))), 14);
2483 assert_eq!(check!(read.read_at(&mut buf, 14)), 0);
2484 assert_eq!(check!(read.read_at(&mut buf, 15)), 0);
2485 assert_eq!(check!(read.seek(SeekFrom::Current(0))), 14);
2487 check!(fs::remove_file(&filename));
2492 fn set_get_unix_permissions() {
2493 use crate::os::unix::fs::PermissionsExt;
2495 let tmpdir = tmpdir();
2496 let filename = &tmpdir.join("set_get_unix_permissions");
2497 check!(fs::create_dir(filename));
2500 check!(fs::set_permissions(filename,
2501 fs::Permissions::from_mode(0)));
2502 let metadata0 = check!(fs::metadata(filename));
2503 assert_eq!(mask & metadata0.permissions().mode(), 0);
2505 check!(fs::set_permissions(filename,
2506 fs::Permissions::from_mode(0o1777)));
2507 let metadata1 = check!(fs::metadata(filename));
2508 assert_eq!(mask & metadata1.permissions().mode(), 0o1777);
2513 fn file_test_io_seek_read_write() {
2514 use crate::os::windows::fs::FileExt;
2516 let tmpdir = tmpdir();
2517 let filename = tmpdir.join("file_rt_io_file_test_seek_read_write.txt");
2518 let mut buf = [0; 256];
2519 let write1 = "asdf";
2520 let write2 = "qwer-";
2521 let write3 = "-zxcv";
2522 let content = "qwer-asdf-zxcv";
2524 let oo = OpenOptions::new().create_new(true).write(true).read(true).clone();
2525 let mut rw = check!(oo.open(&filename));
2526 assert_eq!(check!(rw.seek_write(write1.as_bytes(), 5)), write1.len());
2527 assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 9);
2528 assert_eq!(check!(rw.seek_read(&mut buf, 5)), write1.len());
2529 assert_eq!(str::from_utf8(&buf[..write1.len()]), Ok(write1));
2530 assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 9);
2531 assert_eq!(check!(rw.seek(SeekFrom::Start(0))), 0);
2532 assert_eq!(check!(rw.write(write2.as_bytes())), write2.len());
2533 assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 5);
2534 assert_eq!(check!(rw.read(&mut buf)), write1.len());
2535 assert_eq!(str::from_utf8(&buf[..write1.len()]), Ok(write1));
2536 assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 9);
2537 assert_eq!(check!(rw.seek_read(&mut buf[..write2.len()], 0)), write2.len());
2538 assert_eq!(str::from_utf8(&buf[..write2.len()]), Ok(write2));
2539 assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 5);
2540 assert_eq!(check!(rw.seek_write(write3.as_bytes(), 9)), write3.len());
2541 assert_eq!(check!(rw.seek(SeekFrom::Current(0))), 14);
2544 let mut read = check!(File::open(&filename));
2545 assert_eq!(check!(read.seek_read(&mut buf, 0)), content.len());
2546 assert_eq!(str::from_utf8(&buf[..content.len()]), Ok(content));
2547 assert_eq!(check!(read.seek(SeekFrom::Current(0))), 14);
2548 assert_eq!(check!(read.seek(SeekFrom::End(-5))), 9);
2549 assert_eq!(check!(read.seek_read(&mut buf, 0)), content.len());
2550 assert_eq!(str::from_utf8(&buf[..content.len()]), Ok(content));
2551 assert_eq!(check!(read.seek(SeekFrom::Current(0))), 14);
2552 assert_eq!(check!(read.seek(SeekFrom::End(-5))), 9);
2553 assert_eq!(check!(read.read(&mut buf)), write3.len());
2554 assert_eq!(str::from_utf8(&buf[..write3.len()]), Ok(write3));
2555 assert_eq!(check!(read.seek(SeekFrom::Current(0))), 14);
2556 assert_eq!(check!(read.seek_read(&mut buf, 0)), content.len());
2557 assert_eq!(str::from_utf8(&buf[..content.len()]), Ok(content));
2558 assert_eq!(check!(read.seek(SeekFrom::Current(0))), 14);
2559 assert_eq!(check!(read.seek_read(&mut buf, 14)), 0);
2560 assert_eq!(check!(read.seek_read(&mut buf, 15)), 0);
2562 check!(fs::remove_file(&filename));
2566 fn file_test_stat_is_correct_on_is_file() {
2567 let tmpdir = tmpdir();
2568 let filename = &tmpdir.join("file_stat_correct_on_is_file.txt");
2570 let mut opts = OpenOptions::new();
2571 let mut fs = check!(opts.read(true).write(true)
2572 .create(true).open(filename));
2574 fs.write(msg.as_bytes()).unwrap();
2576 let fstat_res = check!(fs.metadata());
2577 assert!(fstat_res.is_file());
2579 let stat_res_fn = check!(fs::metadata(filename));
2580 assert!(stat_res_fn.is_file());
2581 let stat_res_meth = check!(filename.metadata());
2582 assert!(stat_res_meth.is_file());
2583 check!(fs::remove_file(filename));
2587 fn file_test_stat_is_correct_on_is_dir() {
2588 let tmpdir = tmpdir();
2589 let filename = &tmpdir.join("file_stat_correct_on_is_dir");
2590 check!(fs::create_dir(filename));
2591 let stat_res_fn = check!(fs::metadata(filename));
2592 assert!(stat_res_fn.is_dir());
2593 let stat_res_meth = check!(filename.metadata());
2594 assert!(stat_res_meth.is_dir());
2595 check!(fs::remove_dir(filename));
2599 fn file_test_fileinfo_false_when_checking_is_file_on_a_directory() {
2600 let tmpdir = tmpdir();
2601 let dir = &tmpdir.join("fileinfo_false_on_dir");
2602 check!(fs::create_dir(dir));
2603 assert!(!dir.is_file());
2604 check!(fs::remove_dir(dir));
2608 fn file_test_fileinfo_check_exists_before_and_after_file_creation() {
2609 let tmpdir = tmpdir();
2610 let file = &tmpdir.join("fileinfo_check_exists_b_and_a.txt");
2611 check!(check!(File::create(file)).write(b"foo"));
2612 assert!(file.exists());
2613 check!(fs::remove_file(file));
2614 assert!(!file.exists());
2618 fn file_test_directoryinfo_check_exists_before_and_after_mkdir() {
2619 let tmpdir = tmpdir();
2620 let dir = &tmpdir.join("before_and_after_dir");
2621 assert!(!dir.exists());
2622 check!(fs::create_dir(dir));
2623 assert!(dir.exists());
2624 assert!(dir.is_dir());
2625 check!(fs::remove_dir(dir));
2626 assert!(!dir.exists());
2630 fn file_test_directoryinfo_readdir() {
2631 let tmpdir = tmpdir();
2632 let dir = &tmpdir.join("di_readdir");
2633 check!(fs::create_dir(dir));
2636 let f = dir.join(&format!("{}.txt", n));
2637 let mut w = check!(File::create(&f));
2638 let msg_str = format!("{}{}", prefix, n.to_string());
2639 let msg = msg_str.as_bytes();
2640 check!(w.write(msg));
2642 let files = check!(fs::read_dir(dir));
2643 let mut mem = [0; 4];
2645 let f = f.unwrap().path();
2647 let n = f.file_stem().unwrap();
2648 check!(check!(File::open(&f)).read(&mut mem));
2649 let read_str = str::from_utf8(&mem).unwrap();
2650 let expected = format!("{}{}", prefix, n.to_str().unwrap());
2651 assert_eq!(expected, read_str);
2653 check!(fs::remove_file(&f));
2655 check!(fs::remove_dir(dir));
2659 fn file_create_new_already_exists_error() {
2660 let tmpdir = tmpdir();
2661 let file = &tmpdir.join("file_create_new_error_exists");
2662 check!(fs::File::create(file));
2663 let e = fs::OpenOptions::new().write(true).create_new(true).open(file).unwrap_err();
2664 assert_eq!(e.kind(), ErrorKind::AlreadyExists);
2668 fn mkdir_path_already_exists_error() {
2669 let tmpdir = tmpdir();
2670 let dir = &tmpdir.join("mkdir_error_twice");
2671 check!(fs::create_dir(dir));
2672 let e = fs::create_dir(dir).unwrap_err();
2673 assert_eq!(e.kind(), ErrorKind::AlreadyExists);
2677 fn recursive_mkdir() {
2678 let tmpdir = tmpdir();
2679 let dir = tmpdir.join("d1/d2");
2680 check!(fs::create_dir_all(&dir));
2681 assert!(dir.is_dir())
2685 fn recursive_mkdir_failure() {
2686 let tmpdir = tmpdir();
2687 let dir = tmpdir.join("d1");
2688 let file = dir.join("f1");
2690 check!(fs::create_dir_all(&dir));
2691 check!(File::create(&file));
2693 let result = fs::create_dir_all(&file);
2695 assert!(result.is_err());
2699 fn concurrent_recursive_mkdir() {
2702 let mut dir = dir.join("a");
2704 dir = dir.join("a");
2706 let mut join = vec!();
2708 let dir = dir.clone();
2709 join.push(thread::spawn(move || {
2710 check!(fs::create_dir_all(&dir));
2714 // No `Display` on result of `join()`
2715 join.drain(..).map(|join| join.join().unwrap()).count();
2720 fn recursive_mkdir_slash() {
2721 check!(fs::create_dir_all(Path::new("/")));
2725 fn recursive_mkdir_dot() {
2726 check!(fs::create_dir_all(Path::new(".")));
2730 fn recursive_mkdir_empty() {
2731 check!(fs::create_dir_all(Path::new("")));
2735 fn recursive_rmdir() {
2736 let tmpdir = tmpdir();
2737 let d1 = tmpdir.join("d1");
2738 let dt = d1.join("t");
2739 let dtt = dt.join("t");
2740 let d2 = tmpdir.join("d2");
2741 let canary = d2.join("do_not_delete");
2742 check!(fs::create_dir_all(&dtt));
2743 check!(fs::create_dir_all(&d2));
2744 check!(check!(File::create(&canary)).write(b"foo"));
2745 check!(symlink_junction(&d2, &dt.join("d2")));
2746 let _ = symlink_file(&canary, &d1.join("canary"));
2747 check!(fs::remove_dir_all(&d1));
2749 assert!(!d1.is_dir());
2750 assert!(canary.exists());
2754 fn recursive_rmdir_of_symlink() {
2755 // test we do not recursively delete a symlink but only dirs.
2756 let tmpdir = tmpdir();
2757 let link = tmpdir.join("d1");
2758 let dir = tmpdir.join("d2");
2759 let canary = dir.join("do_not_delete");
2760 check!(fs::create_dir_all(&dir));
2761 check!(check!(File::create(&canary)).write(b"foo"));
2762 check!(symlink_junction(&dir, &link));
2763 check!(fs::remove_dir_all(&link));
2765 assert!(!link.is_dir());
2766 assert!(canary.exists());
2770 // only Windows makes a distinction between file and directory symlinks.
2772 fn recursive_rmdir_of_file_symlink() {
2773 let tmpdir = tmpdir();
2774 if !got_symlink_permission(&tmpdir) { return };
2776 let f1 = tmpdir.join("f1");
2777 let f2 = tmpdir.join("f2");
2778 check!(check!(File::create(&f1)).write(b"foo"));
2779 check!(symlink_file(&f1, &f2));
2780 match fs::remove_dir_all(&f2) {
2781 Ok(..) => panic!("wanted a failure"),
2787 fn unicode_path_is_dir() {
2788 assert!(Path::new(".").is_dir());
2789 assert!(!Path::new("test/stdtest/fs.rs").is_dir());
2791 let tmpdir = tmpdir();
2793 let mut dirpath = tmpdir.path().to_path_buf();
2794 dirpath.push("test-가一ー你好");
2795 check!(fs::create_dir(&dirpath));
2796 assert!(dirpath.is_dir());
2798 let mut filepath = dirpath;
2799 filepath.push("unicode-file-\u{ac00}\u{4e00}\u{30fc}\u{4f60}\u{597d}.rs");
2800 check!(File::create(&filepath)); // ignore return; touch only
2801 assert!(!filepath.is_dir());
2802 assert!(filepath.exists());
2806 fn unicode_path_exists() {
2807 assert!(Path::new(".").exists());
2808 assert!(!Path::new("test/nonexistent-bogus-path").exists());
2810 let tmpdir = tmpdir();
2811 let unicode = tmpdir.path();
2812 let unicode = unicode.join("test-각丁ー再见");
2813 check!(fs::create_dir(&unicode));
2814 assert!(unicode.exists());
2815 assert!(!Path::new("test/unicode-bogus-path-각丁ー再见").exists());
2819 fn copy_file_does_not_exist() {
2820 let from = Path::new("test/nonexistent-bogus-path");
2821 let to = Path::new("test/other-bogus-path");
2823 match fs::copy(&from, &to) {
2826 assert!(!from.exists());
2827 assert!(!to.exists());
2833 fn copy_src_does_not_exist() {
2834 let tmpdir = tmpdir();
2835 let from = Path::new("test/nonexistent-bogus-path");
2836 let to = tmpdir.join("out.txt");
2837 check!(check!(File::create(&to)).write(b"hello"));
2838 assert!(fs::copy(&from, &to).is_err());
2839 assert!(!from.exists());
2840 let mut v = Vec::new();
2841 check!(check!(File::open(&to)).read_to_end(&mut v));
2842 assert_eq!(v, b"hello");
2847 let tmpdir = tmpdir();
2848 let input = tmpdir.join("in.txt");
2849 let out = tmpdir.join("out.txt");
2851 check!(check!(File::create(&input)).write(b"hello"));
2852 check!(fs::copy(&input, &out));
2853 let mut v = Vec::new();
2854 check!(check!(File::open(&out)).read_to_end(&mut v));
2855 assert_eq!(v, b"hello");
2857 assert_eq!(check!(input.metadata()).permissions(),
2858 check!(out.metadata()).permissions());
2862 fn copy_file_dst_dir() {
2863 let tmpdir = tmpdir();
2864 let out = tmpdir.join("out");
2866 check!(File::create(&out));
2867 match fs::copy(&*out, tmpdir.path()) {
2868 Ok(..) => panic!(), Err(..) => {}
2873 fn copy_file_dst_exists() {
2874 let tmpdir = tmpdir();
2875 let input = tmpdir.join("in");
2876 let output = tmpdir.join("out");
2878 check!(check!(File::create(&input)).write("foo".as_bytes()));
2879 check!(check!(File::create(&output)).write("bar".as_bytes()));
2880 check!(fs::copy(&input, &output));
2882 let mut v = Vec::new();
2883 check!(check!(File::open(&output)).read_to_end(&mut v));
2884 assert_eq!(v, b"foo".to_vec());
2888 fn copy_file_src_dir() {
2889 let tmpdir = tmpdir();
2890 let out = tmpdir.join("out");
2892 match fs::copy(tmpdir.path(), &out) {
2893 Ok(..) => panic!(), Err(..) => {}
2895 assert!(!out.exists());
2899 fn copy_file_preserves_perm_bits() {
2900 let tmpdir = tmpdir();
2901 let input = tmpdir.join("in.txt");
2902 let out = tmpdir.join("out.txt");
2904 let attr = check!(check!(File::create(&input)).metadata());
2905 let mut p = attr.permissions();
2906 p.set_readonly(true);
2907 check!(fs::set_permissions(&input, p));
2908 check!(fs::copy(&input, &out));
2909 assert!(check!(out.metadata()).permissions().readonly());
2910 check!(fs::set_permissions(&input, attr.permissions()));
2911 check!(fs::set_permissions(&out, attr.permissions()));
2916 fn copy_file_preserves_streams() {
2918 check!(check!(File::create(tmp.join("in.txt:bunny"))).write("carrot".as_bytes()));
2919 assert_eq!(check!(fs::copy(tmp.join("in.txt"), tmp.join("out.txt"))), 0);
2920 assert_eq!(check!(tmp.join("out.txt").metadata()).len(), 0);
2921 let mut v = Vec::new();
2922 check!(check!(File::open(tmp.join("out.txt:bunny"))).read_to_end(&mut v));
2923 assert_eq!(v, b"carrot".to_vec());
2927 fn copy_file_returns_metadata_len() {
2929 let in_path = tmp.join("in.txt");
2930 let out_path = tmp.join("out.txt");
2931 check!(check!(File::create(&in_path)).write(b"lettuce"));
2933 check!(check!(File::create(tmp.join("in.txt:bunny"))).write(b"carrot"));
2934 let copied_len = check!(fs::copy(&in_path, &out_path));
2935 assert_eq!(check!(out_path.metadata()).len(), copied_len);
2939 fn copy_file_follows_dst_symlink() {
2941 if !got_symlink_permission(&tmp) { return };
2943 let in_path = tmp.join("in.txt");
2944 let out_path = tmp.join("out.txt");
2945 let out_path_symlink = tmp.join("out_symlink.txt");
2947 check!(fs::write(&in_path, "foo"));
2948 check!(fs::write(&out_path, "bar"));
2949 check!(symlink_file(&out_path, &out_path_symlink));
2951 check!(fs::copy(&in_path, &out_path_symlink));
2953 assert!(check!(out_path_symlink.symlink_metadata()).file_type().is_symlink());
2954 assert_eq!(check!(fs::read(&out_path_symlink)), b"foo".to_vec());
2955 assert_eq!(check!(fs::read(&out_path)), b"foo".to_vec());
2959 fn symlinks_work() {
2960 let tmpdir = tmpdir();
2961 if !got_symlink_permission(&tmpdir) { return };
2963 let input = tmpdir.join("in.txt");
2964 let out = tmpdir.join("out.txt");
2966 check!(check!(File::create(&input)).write("foobar".as_bytes()));
2967 check!(symlink_file(&input, &out));
2968 assert!(check!(out.symlink_metadata()).file_type().is_symlink());
2969 assert_eq!(check!(fs::metadata(&out)).len(),
2970 check!(fs::metadata(&input)).len());
2971 let mut v = Vec::new();
2972 check!(check!(File::open(&out)).read_to_end(&mut v));
2973 assert_eq!(v, b"foobar".to_vec());
2977 fn symlink_noexist() {
2978 // Symlinks can point to things that don't exist
2979 let tmpdir = tmpdir();
2980 if !got_symlink_permission(&tmpdir) { return };
2982 // Use a relative path for testing. Symlinks get normalized by Windows,
2983 // so we may not get the same path back for absolute paths
2984 check!(symlink_file(&"foo", &tmpdir.join("bar")));
2985 assert_eq!(check!(fs::read_link(&tmpdir.join("bar"))).to_str().unwrap(),
2992 // directory symlink
2993 assert_eq!(check!(fs::read_link(r"C:\Users\All Users")).to_str().unwrap(),
2996 assert_eq!(check!(fs::read_link(r"C:\Users\Default User")).to_str().unwrap(),
2997 r"C:\Users\Default");
2998 // junction with special permissions
2999 assert_eq!(check!(fs::read_link(r"C:\Documents and Settings\")).to_str().unwrap(),
3002 let tmpdir = tmpdir();
3003 let link = tmpdir.join("link");
3004 if !got_symlink_permission(&tmpdir) { return };
3005 check!(symlink_file(&"foo", &link));
3006 assert_eq!(check!(fs::read_link(&link)).to_str().unwrap(), "foo");
3010 fn readlink_not_symlink() {
3011 let tmpdir = tmpdir();
3012 match fs::read_link(tmpdir.path()) {
3013 Ok(..) => panic!("wanted a failure"),
3020 let tmpdir = tmpdir();
3021 let input = tmpdir.join("in.txt");
3022 let out = tmpdir.join("out.txt");
3024 check!(check!(File::create(&input)).write("foobar".as_bytes()));
3025 check!(fs::hard_link(&input, &out));
3026 assert_eq!(check!(fs::metadata(&out)).len(),
3027 check!(fs::metadata(&input)).len());
3028 assert_eq!(check!(fs::metadata(&out)).len(),
3029 check!(input.metadata()).len());
3030 let mut v = Vec::new();
3031 check!(check!(File::open(&out)).read_to_end(&mut v));
3032 assert_eq!(v, b"foobar".to_vec());
3034 // can't link to yourself
3035 match fs::hard_link(&input, &input) {
3036 Ok(..) => panic!("wanted a failure"),
3039 // can't link to something that doesn't exist
3040 match fs::hard_link(&tmpdir.join("foo"), &tmpdir.join("bar")) {
3041 Ok(..) => panic!("wanted a failure"),
3048 let tmpdir = tmpdir();
3049 let file = tmpdir.join("in.txt");
3051 check!(File::create(&file));
3052 let attr = check!(fs::metadata(&file));
3053 assert!(!attr.permissions().readonly());
3054 let mut p = attr.permissions();
3055 p.set_readonly(true);
3056 check!(fs::set_permissions(&file, p.clone()));
3057 let attr = check!(fs::metadata(&file));
3058 assert!(attr.permissions().readonly());
3060 match fs::set_permissions(&tmpdir.join("foo"), p.clone()) {
3061 Ok(..) => panic!("wanted an error"),
3065 p.set_readonly(false);
3066 check!(fs::set_permissions(&file, p));
3071 let tmpdir = tmpdir();
3072 let path = tmpdir.join("in.txt");
3074 let file = check!(File::create(&path));
3075 let attr = check!(fs::metadata(&path));
3076 assert!(!attr.permissions().readonly());
3077 let mut p = attr.permissions();
3078 p.set_readonly(true);
3079 check!(file.set_permissions(p.clone()));
3080 let attr = check!(fs::metadata(&path));
3081 assert!(attr.permissions().readonly());
3083 p.set_readonly(false);
3084 check!(file.set_permissions(p));
3088 fn sync_doesnt_kill_anything() {
3089 let tmpdir = tmpdir();
3090 let path = tmpdir.join("in.txt");
3092 let mut file = check!(File::create(&path));
3093 check!(file.sync_all());
3094 check!(file.sync_data());
3095 check!(file.write(b"foo"));
3096 check!(file.sync_all());
3097 check!(file.sync_data());
3101 fn truncate_works() {
3102 let tmpdir = tmpdir();
3103 let path = tmpdir.join("in.txt");
3105 let mut file = check!(File::create(&path));
3106 check!(file.write(b"foo"));
3107 check!(file.sync_all());
3109 // Do some simple things with truncation
3110 assert_eq!(check!(file.metadata()).len(), 3);
3111 check!(file.set_len(10));
3112 assert_eq!(check!(file.metadata()).len(), 10);
3113 check!(file.write(b"bar"));
3114 check!(file.sync_all());
3115 assert_eq!(check!(file.metadata()).len(), 10);
3117 let mut v = Vec::new();
3118 check!(check!(File::open(&path)).read_to_end(&mut v));
3119 assert_eq!(v, b"foobar\0\0\0\0".to_vec());
3121 // Truncate to a smaller length, don't seek, and then write something.
3122 // Ensure that the intermediate zeroes are all filled in (we have `seek`ed
3123 // past the end of the file).
3124 check!(file.set_len(2));
3125 assert_eq!(check!(file.metadata()).len(), 2);
3126 check!(file.write(b"wut"));
3127 check!(file.sync_all());
3128 assert_eq!(check!(file.metadata()).len(), 9);
3129 let mut v = Vec::new();
3130 check!(check!(File::open(&path)).read_to_end(&mut v));
3131 assert_eq!(v, b"fo\0\0\0\0wut".to_vec());
3136 use crate::fs::OpenOptions as OO;
3137 fn c<T: Clone>(t: &T) -> T { t.clone() }
3139 let tmpdir = tmpdir();
3141 let mut r = OO::new(); r.read(true);
3142 let mut w = OO::new(); w.write(true);
3143 let mut rw = OO::new(); rw.read(true).write(true);
3144 let mut a = OO::new(); a.append(true);
3145 let mut ra = OO::new(); ra.read(true).append(true);
3148 let invalid_options = 87; // ERROR_INVALID_PARAMETER
3149 #[cfg(all(unix, not(target_os = "vxworks")))]
3150 let invalid_options = "Invalid argument";
3151 #[cfg(target_os = "vxworks")]
3152 let invalid_options = "invalid argument";
3154 // Test various combinations of creation modes and access modes.
3157 // creation mode | read | write | read-write | append | read-append |
3158 // :-----------------------|:-----:|:-----:|:----------:|:------:|:-----------:|
3159 // not set (open existing) | X | X | X | X | X |
3160 // create | | X | X | X | X |
3161 // truncate | | X | X | | |
3162 // create and truncate | | X | X | | |
3163 // create_new | | X | X | X | X |
3165 // tested in reverse order, so 'create_new' creates the file, and 'open existing' opens it.
3168 check!(c(&w).create_new(true).open(&tmpdir.join("a")));
3169 check!(c(&w).create(true).truncate(true).open(&tmpdir.join("a")));
3170 check!(c(&w).truncate(true).open(&tmpdir.join("a")));
3171 check!(c(&w).create(true).open(&tmpdir.join("a")));
3172 check!(c(&w).open(&tmpdir.join("a")));
3175 error!(c(&r).create_new(true).open(&tmpdir.join("b")), invalid_options);
3176 error!(c(&r).create(true).truncate(true).open(&tmpdir.join("b")), invalid_options);
3177 error!(c(&r).truncate(true).open(&tmpdir.join("b")), invalid_options);
3178 error!(c(&r).create(true).open(&tmpdir.join("b")), invalid_options);
3179 check!(c(&r).open(&tmpdir.join("a"))); // try opening the file created with write_only
3182 check!(c(&rw).create_new(true).open(&tmpdir.join("c")));
3183 check!(c(&rw).create(true).truncate(true).open(&tmpdir.join("c")));
3184 check!(c(&rw).truncate(true).open(&tmpdir.join("c")));
3185 check!(c(&rw).create(true).open(&tmpdir.join("c")));
3186 check!(c(&rw).open(&tmpdir.join("c")));
3189 check!(c(&a).create_new(true).open(&tmpdir.join("d")));
3190 error!(c(&a).create(true).truncate(true).open(&tmpdir.join("d")), invalid_options);
3191 error!(c(&a).truncate(true).open(&tmpdir.join("d")), invalid_options);
3192 check!(c(&a).create(true).open(&tmpdir.join("d")));
3193 check!(c(&a).open(&tmpdir.join("d")));
3196 check!(c(&ra).create_new(true).open(&tmpdir.join("e")));
3197 error!(c(&ra).create(true).truncate(true).open(&tmpdir.join("e")), invalid_options);
3198 error!(c(&ra).truncate(true).open(&tmpdir.join("e")), invalid_options);
3199 check!(c(&ra).create(true).open(&tmpdir.join("e")));
3200 check!(c(&ra).open(&tmpdir.join("e")));
3202 // Test opening a file without setting an access mode
3203 let mut blank = OO::new();
3204 error!(blank.create(true).open(&tmpdir.join("f")), invalid_options);
3207 check!(check!(File::create(&tmpdir.join("h"))).write("foobar".as_bytes()));
3209 // Test write fails for read-only
3210 check!(r.open(&tmpdir.join("h")));
3212 let mut f = check!(r.open(&tmpdir.join("h")));
3213 assert!(f.write("wut".as_bytes()).is_err());
3216 // Test write overwrites
3218 let mut f = check!(c(&w).open(&tmpdir.join("h")));
3219 check!(f.write("baz".as_bytes()));
3222 let mut f = check!(c(&r).open(&tmpdir.join("h")));
3223 let mut b = vec![0; 6];
3224 check!(f.read(&mut b));
3225 assert_eq!(b, "bazbar".as_bytes());
3228 // Test truncate works
3230 let mut f = check!(c(&w).truncate(true).open(&tmpdir.join("h")));
3231 check!(f.write("foo".as_bytes()));
3233 assert_eq!(check!(fs::metadata(&tmpdir.join("h"))).len(), 3);
3235 // Test append works
3236 assert_eq!(check!(fs::metadata(&tmpdir.join("h"))).len(), 3);
3238 let mut f = check!(c(&a).open(&tmpdir.join("h")));
3239 check!(f.write("bar".as_bytes()));
3241 assert_eq!(check!(fs::metadata(&tmpdir.join("h"))).len(), 6);
3243 // Test .append(true) equals .write(true).append(true)
3245 let mut f = check!(c(&w).append(true).open(&tmpdir.join("h")));
3246 check!(f.write("baz".as_bytes()));
3248 assert_eq!(check!(fs::metadata(&tmpdir.join("h"))).len(), 9);
3252 fn _assert_send_sync() {
3253 fn _assert_send_sync<T: Send + Sync>() {}
3254 _assert_send_sync::<OpenOptions>();
3259 let mut bytes = [0; 1024];
3260 StdRng::from_entropy().fill_bytes(&mut bytes);
3262 let tmpdir = tmpdir();
3264 check!(check!(File::create(&tmpdir.join("test"))).write(&bytes));
3265 let mut v = Vec::new();
3266 check!(check!(File::open(&tmpdir.join("test"))).read_to_end(&mut v));
3267 assert!(v == &bytes[..]);
3271 fn write_then_read() {
3272 let mut bytes = [0; 1024];
3273 StdRng::from_entropy().fill_bytes(&mut bytes);
3275 let tmpdir = tmpdir();
3277 check!(fs::write(&tmpdir.join("test"), &bytes[..]));
3278 let v = check!(fs::read(&tmpdir.join("test")));
3279 assert!(v == &bytes[..]);
3281 check!(fs::write(&tmpdir.join("not-utf8"), &[0xFF]));
3282 error_contains!(fs::read_to_string(&tmpdir.join("not-utf8")),
3283 "stream did not contain valid UTF-8");
3286 check!(fs::write(&tmpdir.join("utf8"), s.as_bytes()));
3287 let string = check!(fs::read_to_string(&tmpdir.join("utf8")));
3288 assert_eq!(string, s);
3292 fn file_try_clone() {
3293 let tmpdir = tmpdir();
3295 let mut f1 = check!(OpenOptions::new()
3299 .open(&tmpdir.join("test")));
3300 let mut f2 = check!(f1.try_clone());
3302 check!(f1.write_all(b"hello world"));
3303 check!(f1.seek(SeekFrom::Start(2)));
3305 let mut buf = vec![];
3306 check!(f2.read_to_end(&mut buf));
3307 assert_eq!(buf, b"llo world");
3310 check!(f1.write_all(b"!"));
3314 #[cfg(not(windows))]
3315 fn unlink_readonly() {
3316 let tmpdir = tmpdir();
3317 let path = tmpdir.join("file");
3318 check!(File::create(&path));
3319 let mut perm = check!(fs::metadata(&path)).permissions();
3320 perm.set_readonly(true);
3321 check!(fs::set_permissions(&path, perm));
3322 check!(fs::remove_file(&path));
3326 fn mkdir_trailing_slash() {
3327 let tmpdir = tmpdir();
3328 let path = tmpdir.join("file");
3329 check!(fs::create_dir_all(&path.join("a/")));
3333 fn canonicalize_works_simple() {
3334 let tmpdir = tmpdir();
3335 let tmpdir = fs::canonicalize(tmpdir.path()).unwrap();
3336 let file = tmpdir.join("test");
3337 File::create(&file).unwrap();
3338 assert_eq!(fs::canonicalize(&file).unwrap(), file);
3342 fn realpath_works() {
3343 let tmpdir = tmpdir();
3344 if !got_symlink_permission(&tmpdir) { return };
3346 let tmpdir = fs::canonicalize(tmpdir.path()).unwrap();
3347 let file = tmpdir.join("test");
3348 let dir = tmpdir.join("test2");
3349 let link = dir.join("link");
3350 let linkdir = tmpdir.join("test3");
3352 File::create(&file).unwrap();
3353 fs::create_dir(&dir).unwrap();
3354 symlink_file(&file, &link).unwrap();
3355 symlink_dir(&dir, &linkdir).unwrap();
3357 assert!(link.symlink_metadata().unwrap().file_type().is_symlink());
3359 assert_eq!(fs::canonicalize(&tmpdir).unwrap(), tmpdir);
3360 assert_eq!(fs::canonicalize(&file).unwrap(), file);
3361 assert_eq!(fs::canonicalize(&link).unwrap(), file);
3362 assert_eq!(fs::canonicalize(&linkdir).unwrap(), dir);
3363 assert_eq!(fs::canonicalize(&linkdir.join("link")).unwrap(), file);
3367 fn realpath_works_tricky() {
3368 let tmpdir = tmpdir();
3369 if !got_symlink_permission(&tmpdir) { return };
3371 let tmpdir = fs::canonicalize(tmpdir.path()).unwrap();
3372 let a = tmpdir.join("a");
3373 let b = a.join("b");
3374 let c = b.join("c");
3375 let d = a.join("d");
3376 let e = d.join("e");
3377 let f = a.join("f");
3379 fs::create_dir_all(&b).unwrap();
3380 fs::create_dir_all(&d).unwrap();
3381 File::create(&f).unwrap();
3382 if cfg!(not(windows)) {
3383 symlink_file("../d/e", &c).unwrap();
3384 symlink_file("../f", &e).unwrap();
3387 symlink_file(r"..\d\e", &c).unwrap();
3388 symlink_file(r"..\f", &e).unwrap();
3391 assert_eq!(fs::canonicalize(&c).unwrap(), f);
3392 assert_eq!(fs::canonicalize(&e).unwrap(), f);
3396 fn dir_entry_methods() {
3397 let tmpdir = tmpdir();
3399 fs::create_dir_all(&tmpdir.join("a")).unwrap();
3400 File::create(&tmpdir.join("b")).unwrap();
3402 for file in tmpdir.path().read_dir().unwrap().map(|f| f.unwrap()) {
3403 let fname = file.file_name();
3404 match fname.to_str() {
3406 assert!(file.file_type().unwrap().is_dir());
3407 assert!(file.metadata().unwrap().is_dir());
3410 assert!(file.file_type().unwrap().is_file());
3411 assert!(file.metadata().unwrap().is_file());
3413 f => panic!("unknown file name: {:?}", f),
3419 fn dir_entry_debug() {
3420 let tmpdir = tmpdir();
3421 File::create(&tmpdir.join("b")).unwrap();
3422 let mut read_dir = tmpdir.path().read_dir().unwrap();
3423 let dir_entry = read_dir.next().unwrap().unwrap();
3424 let actual = format!("{:?}", dir_entry);
3425 let expected = format!("DirEntry({:?})", dir_entry.0.path());
3426 assert_eq!(actual, expected);
3430 fn read_dir_not_found() {
3431 let res = fs::read_dir("/path/that/does/not/exist");
3432 assert_eq!(res.err().unwrap().kind(), ErrorKind::NotFound);
3436 fn create_dir_all_with_junctions() {
3437 let tmpdir = tmpdir();
3438 let target = tmpdir.join("target");
3440 let junction = tmpdir.join("junction");
3441 let b = junction.join("a/b");
3443 let link = tmpdir.join("link");
3444 let d = link.join("c/d");
3446 fs::create_dir(&target).unwrap();
3448 check!(symlink_junction(&target, &junction));
3449 check!(fs::create_dir_all(&b));
3450 // the junction itself is not a directory, but `is_dir()` on a Path
3452 assert!(junction.is_dir());
3453 assert!(b.exists());
3455 if !got_symlink_permission(&tmpdir) { return };
3456 check!(symlink_dir(&target, &link));
3457 check!(fs::create_dir_all(&d));
3458 assert!(link.is_dir());
3459 assert!(d.exists());
3463 fn metadata_access_times() {
3464 let tmpdir = tmpdir();
3466 let b = tmpdir.join("b");
3467 File::create(&b).unwrap();
3469 let a = check!(fs::metadata(&tmpdir.path()));
3470 let b = check!(fs::metadata(&b));
3472 assert_eq!(check!(a.accessed()), check!(a.accessed()));
3473 assert_eq!(check!(a.modified()), check!(a.modified()));
3474 assert_eq!(check!(b.accessed()), check!(b.modified()));
3476 if cfg!(target_os = "macos") || cfg!(target_os = "windows") {
3477 check!(a.created());
3478 check!(b.created());
3481 if cfg!(target_os = "linux") {
3482 // Not always available
3483 match (a.created(), b.created()) {
3484 (Ok(t1), Ok(t2)) => assert!(t1 <= t2),
3485 (Err(e1), Err(e2)) if e1.kind() == ErrorKind::Other &&
3486 e2.kind() == ErrorKind::Other => {}
3488 "creation time must be always supported or not supported: {:?} {:?}",