Handle – handle base class¶
-
class
uv.
Handle
(uv_handle, loop=None)[source]¶ Handles represent long-lived objects capable of performing certain operations while active. This is the base class of all handles except the file and SSL handle, which are pure Python.
Raises: uv.LoopClosedError – loop has already been closed
Parameters: - loop (Loop) – loop where the handle should run on
- uv_handle (ffi.CData) – allocated c struct for this handle
-
loop
¶ Loop where the handle is running on.
Readonly: True Type: Loop
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on_closed
¶ Callback which should be called after the handle has been closed.
Readonly: False Type: (Handle) -> None
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closed
¶ Handle has been closed. This is True right after the close callback has been called. It means all internal resources are freed and this handle is ready to be garbage collected.
Readonly: True Type: bool
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closing
¶ Handle is already closed or is closing. This is True right after close has been called. Operations on a closed or closing handle will raise
uv.HandleClosedError
.Readonly: True Type: bool
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active
¶ Handle is active or not. What “active” means depends on the handle:
uv.Async
: is always active and cannot be deactivateduv.Pipe
,uv.TCP
,uv.UDP
, ...: basically any handle dealing with IO is active when it is doing something involves IO like reading, writing, connecting or listeninguv.Check
,uv.Idle
,uv.Timer
, ...: handle is active when it has been started and not yet stopped
Readonly: True Type: bool
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referenced
¶ Handle is referenced or not. If the event loop runs in default mode it will exit when there are no more active and referenced handles left. This has nothing to do with CPython’s reference counting.
Readonly: False Type: bool
-
send_buffer_size
¶ Size of the send buffer that the operating system uses for the socket. The following handles are supported: TCP and UDP handles on Unix and Windows, Pipe handles only on Unix. On all unsupported handles this will raise
uv.UVError
with StatusCode.EINVAL.Note
Unlike libuv this library abstracts the different behaviours on Linux and other operating systems. This means, the size set is divided by two on Linux because Linux internally multiplies it by two.
Raises: - uv.UVError – error while getting/setting the send buffer size
- uv.HandleClosedError – handle has already been closed or is closing
Readonly: False
Type: int
-
receive_buffer_size
¶ Size of the receive buffer that the operating system uses for the socket. The following handles are supported: TCP and UDP handles on Unix and Windows, Pipe handles only on Unix. On all unsupported handles this will raise
uv.UVError
with StatusCode.EINVAL.Note
Unlike libuv this library abstracts the different behaviours on Linux and other operating systems. This means, the size set is divided by two on Linux because Linux internally multiplies it by two.
Raises: - uv.UVError – error while getting/setting the receive buffer size
- uv.HandleClosedError – handle has already been closed or is closing
Readonly: False
Type: int
-
fileno
()[source]¶ Gets the platform dependent file descriptor equivalent. The following handles are supported: TCP, UDP, TTY, Pipes and Poll. On all other handles this will raise
uv.UVError
with StatusCode.EINVAL.If a handle does not have an attached file descriptor yet this method will raise
uv.UVError
with StatusCode.EBADF.Warning
Be very careful when using this method. Libuv assumes it is in control of the file descriptor so any change to it may result in unpredictable malfunctions.
Raises: - uv.UVError – error while receiving fileno
- uv.HandleClosedError – handle has already been closed or is closing
Returns: platform dependent file descriptor equivalent
Return type:
-
reference
()[source]¶ References the handle. If the event loop runs in default mode it will exit when there are no more active and referenced handles left. This has nothing to do with CPython’s reference counting. References are idempotent, that is, if a handle is already referenced calling this method again will have not effect.
Raises: uv.HandleClosedError – handle has already been closed or is closing
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dereference
()[source]¶ Dereferences the handle. If the event loop runs in default mode it will exit when there are no more active and referenced handles left. This has nothing to do with CPython’s reference counting. References are idempotent, that is, if a handle is not referenced calling this method again will have not effect.
Raises: uv.HandleClosedError – handle has already been closed or is closing
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close
(on_closed=None)[source]¶ Closes the handle and frees all resources afterwards. Please make sure to call this method on any handle you do not need anymore. Handles do not close automatically and are also not garbage collected unless you have closed them exlicitly (explicit is better than implicit). This method is idempotent, that is, if the handle is already closed or is closing calling this method will have no effect.
In-progress requests, like
uv.ConnectRequest
oruv.WriteRequest
, are cancelled and have their callbacks called asynchronously withStatusCode.ECANCELED
After this method has been called on a handle no other operations can be performed on it, they will raise
uv.HandleClosedError
.Parameters: on_closed ((Handle) -> None) – callback called after the handle has been closed