gio::prelude

Trait PollableInputStreamExt

Source 
pub trait PollableInputStreamExt:
    IsA<PollableInputStream>
    + Sealed
    + 'static {
    // Provided methods
    fn can_poll(&self) -> bool { ... }
    fn is_readable(&self) -> bool { ... }
}
Expand description

Trait containing all PollableInputStream methods.

§Implementors

ConverterInputStream, MemoryInputStream, PollableInputStream, UnixInputStream

Provided Methods§

Source

fn can_poll(&self) -> bool

Checks if @self is actually pollable. Some classes may implement #GPollableInputStream but have only certain instances of that class be pollable. If this method returns false, then the behavior of other #GPollableInputStream methods is undefined.

For any given stream, the value returned by this method is constant; a stream cannot switch from pollable to non-pollable or vice versa.

§Returns

true if @self is pollable, false if not.

Source

fn is_readable(&self) -> bool

Checks if @self can be read.

Note that some stream types may not be able to implement this 100% reliably, and it is possible that a call to g_input_stream_read() after this returns true would still block. To guarantee non-blocking behavior, you should always use g_pollable_input_stream_read_nonblocking(), which will return a IOErrorEnum::WouldBlock error rather than blocking.

The behaviour of this method is undefined if g_pollable_input_stream_can_poll() returns false for @self.

§Returns

true if @self is readable, false if not. If an error has occurred on @self, this will result in g_pollable_input_stream_is_readable() returning true, and the next attempt to read will return the error.

Dyn Compatibility§

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementors§