Trait std::os::windows::fs::OpenOptionsExt1.10.0 [−] [src]

pub trait OpenOptionsExt {
    fn access_mode(&mut self, access: u32) -> &mut Self;

    fn share_mode(&mut self, val: u32) -> &mut Self;

    fn custom_flags(&mut self, flags: u32) -> &mut Self;

    fn attributes(&mut self, val: u32) -> &mut Self;

    fn security_qos_flags(&mut self, flags: u32) -> &mut OpenOptions;
}
This is supported on Windows only.

Windows-specific extensions to OpenOptions.

Required Methods

ⓘImportant traits for &'a mut I

This is supported on Windows only.

Overrides the dwDesiredAccess argument to the call to CreateFile with the specified value.

This will override the read, write, and append flags on the OpenOptions structure. This method provides fine-grained control over the permissions to read, write and append data, attributes (like hidden and system), and extended attributes.

Examples

use std::fs::OpenOptions;
use std::os::windows::prelude::*;

// Open without read and write permission, for example if you only need
// to call `stat` on the file
let file = OpenOptions::new().access_mode(0).open("foo.txt");Run
ⓘImportant traits for &'a mut I

This is supported on Windows only.

Overrides the dwShareMode argument to the call to CreateFile with the specified value.

By default share_mode is set to FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE. This allows other processes to to read, write, and delete/rename the same file while it is open. Removing any of the flags will prevent other processes from performing the corresponding operation until the file handle is closed.

Examples

use std::fs::OpenOptions;
use std::os::windows::prelude::*;

// Do not allow others to read or modify this file while we have it open
// for writing.
let file = OpenOptions::new()
    .write(true)
    .share_mode(0)
    .open("foo.txt");Run
ⓘImportant traits for &'a mut I

This is supported on Windows only.

Sets extra flags for the dwFileFlags argument to the call to CreateFile2 to the specified value (or combines it with attributes and security_qos_flags to set the dwFlagsAndAttributes for CreateFile).

Custom flags can only set flags, not remove flags set by Rust's options. This option overwrites any previously set custom flags.

Examples

extern crate winapi;

use std::fs::OpenOptions;
use std::os::windows::prelude::*;

let file = OpenOptions::new()
    .create(true)
    .write(true)
    .custom_flags(winapi::FILE_FLAG_DELETE_ON_CLOSE)
    .open("foo.txt");Run
ⓘImportant traits for &'a mut I

This is supported on Windows only.

Sets the dwFileAttributes argument to the call to CreateFile2 to the specified value (or combines it with custom_flags and security_qos_flags to set the dwFlagsAndAttributes for CreateFile).

If a new file is created because it does not yet exist and .create(true) or .create_new(true) are specified, the new file is given the attributes declared with .attributes().

If an existing file is opened with .create(true).truncate(true), its existing attributes are preserved and combined with the ones declared with .attributes().

In all other cases the attributes get ignored.

Examples

extern crate winapi;

use std::fs::OpenOptions;
use std::os::windows::prelude::*;

let file = OpenOptions::new()
    .write(true)
    .create(true)
    .attributes(winapi::FILE_ATTRIBUTE_HIDDEN)
    .open("foo.txt");Run

This is supported on Windows only.

Sets the dwSecurityQosFlags argument to the call to CreateFile2 to the specified value (or combines it with custom_flags and attributes to set the dwFlagsAndAttributes for CreateFile).

By default, security_qos_flags is set to SECURITY_ANONYMOUS. For information about possible values, see Impersonation Levels on the Windows Dev Center site.

Examples

use std::fs::OpenOptions;
use std::os::windows::prelude::*;

let file = OpenOptions::new()
    .write(true)
    .create(true)

    // Sets the flag value to `SecurityIdentification`.
    .security_qos_flags(1)

    .open("foo.txt");Run

Implementors