dragon.mpbridge.reduction

Dragon’s replacements for Multiprocessings ‘reduction’ module.

To prevent users from sharing file descriptors between child processes, we always raise an exception.

See the documentation ‘Multiprocessing with Dragon’.

raises NotImplementedError:

Always raise this.

Functions

dragon_DupFd(fd)	Duplicates a file descriptor for a child process in Multiprocessing.
dragon_recvfds(sock, size)	Receive a list of file descriptors from another process via a socket.
dragon_sendfds(sock, fds)	Send an array of file descriptors to another process via a socket.

dragon_DupFd(fd: int) → int

Duplicates a file descriptor for a child process in Multiprocessing.

Dragon does not support sharing file descriptors as it does not generalize to multi-node or federated systems.

See the documentation ‘Multiprocessing with Dragon’.

Parameters:

fd (int) – the file descriptor of the parent process to be duplicated

Returns:

the duplicated file descriptor

Return type:

int

Raises:

NotImplementedError – Always raises an exception.

dragon_sendfds(sock: socket, fds: array) → None

Send an array of file descriptors to another process via a socket.

Dragon does not support this behaviour as it does not generalize to multi-node or federated systems.

See the documentation ‘Multiprocessing with Dragon’.

Parameters:

• sock (socket.socket) – the socket to be used for sending

• fds (array.array) – the array of file descriptors

Raises:

NotImplementedError – Always raises an exception.

dragon_recvfds(sock: socket, size: int) → list

Receive a list of file descriptors from another process via a socket.

Dragon does not support this behaviour as it does not generalize to multi-node or federated systems.

See the documentation ‘Multiprocessing with Dragon’.

Parameters:

• sock (socket.socket) – the socket to be used for sending

• size (int) – the number of file descriptor to receive.

Raises:

NotImplementedError – Always raises an exception.

Returns:

the file descriptors

Return type:

list