Trait tokio::fs::os::unix::OpenOptionsExt

source · [−]
pub trait OpenOptionsExt {
    fn mode(&mut self, mode: u32) -> &mut Self;

    fn custom_flags(&mut self, flags: i32) -> &mut Self;
}
Expand description

Unix-specific extensions to fs::OpenOptions.

This mirrors the definition of std::os::unix::fs::OpenOptionsExt.

Required methods

Sets the mode bits that a new file will be created with.

If a new file is created as part of an OpenOptions::open call then this specified mode will be used as the permission bits for the new file. If no mode is set, the default of 0o666 will be used. The operating system masks out bits with the system’s umask, to produce the final permissions.

Examples
use tokio::fs::OpenOptions;
use tokio::fs::os::unix::OpenOptionsExt;
use std::io;

#[tokio::main]
async fn main() -> io::Result<()> {
    let mut options = OpenOptions::new();
    options.mode(0o644); // Give read/write for owner and read for others.
    let file = options.open("foo.txt").await?;

    Ok(())
}

Pass custom flags to the flags argument of open.

The bits that define the access mode are masked out with O_ACCMODE, to ensure they do not interfere with the access mode set by Rusts options.

Custom flags can only set flags, not remove flags set by Rusts options. This options overwrites any previously set custom flags.

Examples
use libc;
use tokio::fs::OpenOptions;
use tokio::fs::os::unix::OpenOptionsExt;
use std::io;

#[tokio::main]
async fn main() -> io::Result<()> {
    let mut options = OpenOptions::new();
    options.write(true);
    if cfg!(unix) {
        options.custom_flags(libc::O_NOFOLLOW);
    }
    let file = options.open("foo.txt").await?;

    Ok(())
}

Implementors