From e7dc177442e7c91ea0c691a992a634ac879db16f Mon Sep 17 00:00:00 2001 From: darklyspaced Date: Thu, 20 Jul 2023 11:27:13 +0800 Subject: [PATCH] fix docs & example for FileExt::write_at --- library/std/src/os/unix/fs.rs | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/library/std/src/os/unix/fs.rs b/library/std/src/os/unix/fs.rs index 1e1c3693105..358ab33fffd 100644 --- a/library/std/src/os/unix/fs.rs +++ b/library/std/src/os/unix/fs.rs @@ -149,7 +149,14 @@ fn read_exact_at(&self, mut buf: &mut [u8], mut offset: u64) -> io::Result<()> { /// Note that similar to [`File::write`], it is not an error to return a /// short write. /// + /// # Bug + /// On some systems, due to a [bug] with [`pwrite64`] (the underlying + /// syscall), files opened with the `O_APPEND` flag fail to respect the + /// offset parameter, always appending to the end of the file instead. + /// /// [`File::write`]: fs::File::write + /// [`pwrite64`]: https://man7.org/linux/man-pages/man2/pwrite.2.html + /// [bug]: https://man7.org/linux/man-pages/man2/pwrite.2.html#BUGS /// /// # Examples /// @@ -159,7 +166,7 @@ fn read_exact_at(&self, mut buf: &mut [u8], mut offset: u64) -> io::Result<()> { /// use std::os::unix::prelude::FileExt; /// /// fn main() -> io::Result<()> { - /// let file = File::open("foo.txt")?; + /// let file = File::create("foo.txt")?; /// /// // We now write at the offset 10. /// file.write_at(b"sushi", 10)?;