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AsyncFile

An async file-like object for reading and writing data.

Created by the open method of the AsyncOperator class.

closed property #

Whether this file is closed.

Returns:

Type Description
coroutine

An awaitable that returns True if this file is closed.

close() #

Close this file.

This also flushes write buffers, if applicable.

Notes

A closed file cannot be used for further I/O operations.

read(size=None) #

Read at most size bytes from this file asynchronously.

If size is not specified, read until EOF.

Parameters:

Name Type Description Default
size int

The maximum number of bytes to read.

None
Notes

Fewer bytes may be returned than requested, read in a loop to ensure all bytes are read.

Returns:

Type Description
coroutine

An awaitable that returns the bytes read from the stream.

readable() #

Whether this file can be read from.

Returns:

Type Description
coroutine

An awaitable that returns True if this file can be read from.

seek(pos, whence=0) #

Change the position of this file to the given byte offset.

Parameters:

Name Type Description Default
pos int

The byte offset (position) to set.

required
whence int

The reference point for the offset. 0: start of file (default); 1: current position; 2: end of file.

0

Returns:

Type Description
coroutine

An awaitable that returns the current absolute position.

seekable() #

Whether this file can be repositioned.

Notes

This is only applicable to readable files.

Returns:

Type Description
coroutine

An awaitable that returns True if this file can be repositioned.

tell() #

Return the current position of this file.

Returns:

Type Description
coroutine

An awaitable that returns the current absolute position.

writable() #

Whether this file can be written to.

Returns:

Type Description
coroutine

An awaitable that returns True if this file can be written to.

write(bs) #

Write bytes to this file asynchronously.

Parameters:

Name Type Description Default
bs bytes

The bytes to write to the file.

required

Returns:

Type Description
coroutine

An awaitable that returns the number of bytes written.