gio.BufferedInputStream
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gio.BufferedInputStream

gio.BufferedInputStream — Buffered Input Stream

Synopsis

class gio.BufferedInputStream(gio.FilterInputStream):
    gio.BufferedInputStream(base_stream)
    def fill(count, cancellable=None)
    def fill_async(count, callback, io_priority=glib.PRIORITY_DEFAULT, cancellable=None, user_data=None)
    def fill_finish(result)
    def get_available()
    def get_buffer_size()
    def read_byte(cancellable=None)
    def set_buffer_size(size)
Functions
 
    def gio.buffered_input_stream_new_sized(size)

Ancestry

+-- gobject.GObject
  +-- gio.InputStream
    +-- gio.FilterInputStream
      +-- gio.BufferedInputStream

gio.BufferedInputStream Properties

"buffer-size"Read - Write - ConstructThe size of the backend buffer. Allowed values: >= 1. Default value: 4096.

Description

gio.BufferedInputStream implements gio.FilterInputStream and provides for buffered reads.

By default, gio.BufferedInputStream's buffer size is set at 4 kilobytes.

To create a buffered input stream, use gio.BufferedInputStream(), or gio.buffered_input_stream_new_sized() to specify the buffer's size at construction.

To get the size of a buffer within a buffered input stream, use get_buffer_size(). To change the size of a buffered input stream's buffer, use set_buffer_size(). Note that the buffer's size cannot be reduced below the size of the data within the buffer.

Constructor

    gio.BufferedInputStream(base_stream)

base_stream :

a gio.InputStream.

Returns :

a new gio.InputStream for the given base_stream.

Creates a new gio.InputStream from the given base_stream, with a buffer set to the default size (4 kilobytes).

Methods

gio.BufferedInputStream.fill

    def fill(count, cancellable=None)

count :

the number of bytes that will be read from the stream.

cancellable :

optional gio.Cancellable object, None to ignore.

Returns :

the number of bytes read into stream's buffer, up to count, or -1 on error.

The fill() method tries to read count bytes from the stream into the buffer. Will block during this read.

If count is zero, returns zero and does nothing. A value of count larger than G_MAXSSIZE will cause a gio.ERROR_INVALID_ARGUMENT error.

On success, the number of bytes read into the buffer is returned. 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. Zero is returned on end of file (or if count is zero), but never otherwise.

If count is -1 then the attempted read size is equal to the number of bytes that are required to fill the buffer.

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 gio.ERROR_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 -1 is returned and error is set accordingly.

For the asynchronous, non-blocking, version of this function, see gio.BufferedInputStream.fill_async().

gio.BufferedInputStream.fill_async

    def fill_async(count, callback, io_priority=glib.PRIORITY_DEFAULT, cancellable=None, user_data=None)

count :

the number of bytes that will be read from the stream.

callback :

a GAsyncReadyCallback to call when the request is satisfied.

io_priority :

the Glib Priority Constants of the request.

cancellable :

optional gio.Cancellable object, None to ignore.

user_data :

the data to pass to callback function.

The fill_async() method reads data into stream's buffer asynchronously, up to count size. io_priority can be used to prioritize reads.

For the synchronous version of this function, see gio.BufferedInputStream.fill().

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 gio.ERROR_CANCELLED will be set

If count is -1 then the attempted read size is equal to the number of bytes that are required to fill the buffer.

gio.BufferedInputStream.fill_finish

    def fill_finish(result)

result :

a gio.AsyncResult.

Returns :

the size of the read stream, or -1 on an error.

The fill_finish() method finishes an asynchronous file append operation started with gio.BufferedInputStream.fill_async().

gio.BufferedInputStream.get_available

    def get_available()

Returns :

size of the available stream.

The get_available() method gets the size of the available data within the stream.

gio.BufferedInputStream.get_buffer_size

    def get_buffer_size()

Returns :

the current buffer size.

The get_buffer_size() method gets the size of the input buffer.

gio.BufferedInputStream.read_byte

    def read_byte(cancellable=None)

cancellable :

optional gio.Cancellable object, None to ignore.

Returns :

the byte read from the stream, or -1 on end of stream or error.

The read_byte() method tries to read a single byte from the stream or the buffer. Will block during this read.

On success, the byte read from the stream is returned. On end of stream -1 is returned but it's not an exceptional error and error is not set.

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 gio.ERROR_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 -1 is returned and error is set accordingly.

gio.BufferedInputStream.set_buffer_size

    def set_buffer_size(size)

size :

the new buffer size.

The set_buffer_size() method sets the size of the internal buffer of stream to size, or to the size of the contents of the buffer. The buffer can never be resized smaller than its current contents.

Functions

gio.buffered_input_stream_new_sized

    def buffered_input_stream_new_sized(size)

size :

the requested buffer size.

Returns :

A new gio.InputStream.

The buffered_input_stream_new_sized() function creates a new gio.BufferedInputStream from the given base_stream, with a buffer set to size.

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