Trait gio::prelude::InputStreamExt

pub trait InputStreamExt: 'static {
    // Required methods
    fn clear_pending(&self);
    fn close(
        &self,
        cancellable: Option<&impl IsA<Cancellable>>
    ) -> Result<(), Error>;
    fn close_async<P: FnOnce(Result<(), Error>) + 'static>(
        &self,
        io_priority: Priority,
        cancellable: Option<&impl IsA<Cancellable>>,
        callback: P
    );
    fn close_future(
        &self,
        io_priority: Priority
    ) -> Pin<Box_<dyn Future<Output = Result<(), Error>> + 'static>>;
    fn has_pending(&self) -> bool;
    fn is_closed(&self) -> bool;
    fn read_bytes(
        &self,
        count: usize,
        cancellable: Option<&impl IsA<Cancellable>>
    ) -> Result<Bytes, Error>;
    fn read_bytes_async<P: FnOnce(Result<Bytes, Error>) + 'static>(
        &self,
        count: usize,
        io_priority: Priority,
        cancellable: Option<&impl IsA<Cancellable>>,
        callback: P
    );
    fn read_bytes_future(
        &self,
        count: usize,
        io_priority: Priority
    ) -> Pin<Box_<dyn Future<Output = Result<Bytes, Error>> + 'static>>;
    fn set_pending(&self) -> Result<(), Error>;
    fn skip(
        &self,
        count: usize,
        cancellable: Option<&impl IsA<Cancellable>>
    ) -> Result<isize, Error>;
    fn skip_async<P: FnOnce(Result<isize, Error>) + 'static>(
        &self,
        count: usize,
        io_priority: Priority,
        cancellable: Option<&impl IsA<Cancellable>>,
        callback: P
    );
    fn skip_future(
        &self,
        count: usize,
        io_priority: Priority
    ) -> Pin<Box_<dyn Future<Output = Result<isize, Error>> + 'static>>;
}

Trait containing all InputStream methods.

Implementors

FileInputStream, FilterInputStream, InputStream, MemoryInputStream, PollableInputStream, UnixInputStream

Required Methods

fn clear_pending(&self)

Clears the pending flag on self.

fn close( &self, cancellable: Option<&impl IsA<Cancellable>> ) -> Result<(), Error>

Closes the stream, releasing resources related to it.

Once the stream is closed, all other operations will return IOErrorEnum::Closed. Closing a stream multiple times will not return an error.

Streams will be automatically closed when the last reference is dropped, but you might want to call this function to make sure resources are released as early as possible.

Some streams might keep the backing store of the stream (e.g. a file descriptor) open after the stream is closed. See the documentation for the individual stream for details.

On failure the first error that happened will be reported, but the close operation will finish as much as possible. A stream that failed to close will still return IOErrorEnum::Closed for all operations. Still, it is important to check and report the error to the user.

If cancellable is not None, then the operation can be cancelled by triggering the cancellable object from another thread. If the operation was cancelled, the error IOErrorEnum::Cancelled will be returned. Cancelling a close will still leave the stream closed, but some streams can use a faster close that doesn’t block to e.g. check errors.

cancellable

optional Cancellable object, None to ignore.

Returns

true on success, false on failure

fn close_async<P: FnOnce(Result<(), Error>) + 'static>( &self, io_priority: Priority, cancellable: Option<&impl IsA<Cancellable>>, callback: P )

Requests an asynchronous closes of the stream, releasing resources related to it. When the operation is finished callback will be called. You can then call g_input_stream_close_finish() to get the result of the operation.

For behaviour details see close().

The asynchronous methods have a default fallback that uses threads to implement asynchronicity, so they are optional for inheriting classes. However, if you override one you must override all.

io_priority

the [I/O priority][io-priority] of the request

cancellable

optional cancellable object

callback

callback to call when the request is satisfied

fn close_future( &self, io_priority: Priority ) -> Pin<Box_<dyn Future<Output = Result<(), Error>> + 'static>>

fn has_pending(&self) -> bool

Checks if an input stream has pending actions.

Returns

true if self has pending actions.

fn is_closed(&self) -> bool

Checks if an input stream is closed.

Returns

true if the stream is closed.

fn read_bytes( &self, count: usize, cancellable: Option<&impl IsA<Cancellable>> ) -> Result<Bytes, Error>

Like InputStreamExtManual::read(), this tries to read count bytes from the stream in a blocking fashion. However, rather than reading into a user-supplied buffer, this will create a new glib::Bytes containing the data that was read. This may be easier to use from language bindings.

If count is zero, returns a zero-length glib::Bytes and does nothing. A value of count larger than G_MAXSSIZE will cause a IOErrorEnum::InvalidArgument error.

On success, a new glib::Bytes is returned. It is not an error if the size of this object is not the same as the requested size, as it can happen e.g. near the end of a file. A zero-length glib::Bytes is returned on end of file (or if count is zero), but never otherwise.

If cancellable is not None, then the operation can be cancelled by triggering the cancellable object from another thread. If the operation was cancelled, the error IOErrorEnum::Cancelled will be returned. If an operation was partially finished when the operation was cancelled the partial result will be returned, without an error.

On error None is returned and error is set accordingly.

count

maximum number of bytes that will be read from the stream. Common values include 4096 and 8192.

cancellable

optional Cancellable object, None to ignore.

Returns

a new glib::Bytes, or None on error

fn read_bytes_async<P: FnOnce(Result<Bytes, Error>) + 'static>( &self, count: usize, io_priority: Priority, cancellable: Option<&impl IsA<Cancellable>>, callback: P )

Request an asynchronous read of count bytes from the stream into a new glib::Bytes. When the operation is finished callback will be called. You can then call g_input_stream_read_bytes_finish() to get the result of the operation.

During an async request no other sync and async calls are allowed on self, and will result in IOErrorEnum::Pending errors.

A value of count larger than G_MAXSSIZE will cause a IOErrorEnum::InvalidArgument error.

On success, the new glib::Bytes will be passed to the callback. It is not an error if this is smaller than the requested size, as it can happen e.g. near the end of a file, but generally we try to read as many bytes as requested. Zero is returned on end of file (or if count is zero), but never otherwise.

Any outstanding I/O request with higher priority (lower numerical value) will be executed before an outstanding request with lower priority. Default priority is G_PRIORITY_DEFAULT.

count

the number of bytes that will be read from the stream

io_priority

the [I/O priority][io-priority] of the request

cancellable

optional Cancellable object, None to ignore.

callback

callback to call when the request is satisfied

fn read_bytes_future( &self, count: usize, io_priority: Priority ) -> Pin<Box_<dyn Future<Output = Result<Bytes, Error>> + 'static>>

fn set_pending(&self) -> Result<(), Error>

Sets self to have actions pending. If the pending flag is already set or self is closed, it will return false and set error.

Returns

true if pending was previously unset and is now set.

fn skip( &self, count: usize, cancellable: Option<&impl IsA<Cancellable>> ) -> Result<isize, Error>

Tries to skip count bytes from the stream. Will block during the operation.

This is identical to InputStreamExtManual::read(), from a behaviour standpoint, but the bytes that are skipped are not returned to the user. Some streams have an implementation that is more efficient than reading the data.

This function is optional for inherited classes, as the default implementation emulates it using read.

If cancellable is not None, then the operation can be cancelled by triggering the cancellable object from another thread. If the operation was cancelled, the error IOErrorEnum::Cancelled will be returned. If an operation was partially finished when the operation was cancelled the partial result will be returned, without an error.

count

the number of bytes that will be skipped from the stream

cancellable

optional Cancellable object, None to ignore.

Returns

Number of bytes skipped, or -1 on error

fn skip_async<P: FnOnce(Result<isize, Error>) + 'static>( &self, count: usize, io_priority: Priority, cancellable: Option<&impl IsA<Cancellable>>, callback: P )

Request an asynchronous skip of count bytes from the stream. When the operation is finished callback will be called. You can then call g_input_stream_skip_finish() to get the result of the operation.

During an async request no other sync and async calls are allowed, and will result in IOErrorEnum::Pending errors.

A value of count larger than G_MAXSSIZE will cause a IOErrorEnum::InvalidArgument error.

On success, the number of bytes skipped will be passed to the callback. It is not an error if this is not the same as the requested size, as it can happen e.g. near the end of a file, but generally we try to skip as many bytes as requested. Zero is returned on end of file (or if count is zero), but never otherwise.

Any outstanding i/o request with higher priority (lower numerical value) will be executed before an outstanding request with lower priority. Default priority is G_PRIORITY_DEFAULT.

The asynchronous methods have a default fallback that uses threads to implement asynchronicity, so they are optional for inheriting classes. However, if you override one, you must override all.

count

the number of bytes that will be skipped from the stream

io_priority

the [I/O priority][io-priority] of the request

cancellable

optional Cancellable object, None to ignore.

callback

callback to call when the request is satisfied

fn skip_future( &self, count: usize, io_priority: Priority ) -> Pin<Box_<dyn Future<Output = Result<isize, Error>> + 'static>>

Implementors

impl<O: IsA<InputStream>> InputStreamExt for O