file.random_access

Functions

new() → file.random_access

new()                    (1)
new(fd: file_descriptor) (2)
1 Default constructor.
2 Converts a file descriptor into a file.random_access object.

open(self, path: filesystem.path, flags: integer)

Open the file using the specified path.

flags is an or-combination of values from file.open_flag(3em).

close(self)

Close the file.

Any asynchronous read or write operations will be cancelled immediately, and will complete with the boost::asio::error::operation_aborted error.

cancel(self)

Cancel all asynchronous operations associated with the file.

This function causes all outstanding asynchronous read and write operations to finish immediately, and the handlers for cancelled operations will be passed the boost::asio::error::operation_aborted error.

assign(self, fd: file_descriptor)

Assign an existing native file to self.

release(self) → file_descriptor

Release ownership of the native descriptor implementation.

This function causes all outstanding asynchronous read and write operations to finish immediately, and the handlers for cancelled operations will be passed the boost::asio::error::operation_aborted error. Ownership of the native file is then transferred to the caller.

resize(self, n: integer)

Alter the size of the file.

This function resizes the file to the specified size, in bytes. If the current file size exceeds n then any extra data is discarded. If the current size is less than n then the file is extended and filled with zeroes

read_some_at(self, offset: integer, buffer: byte_span) → integer

Read data from the file at the specified offset and blocks current fiber until it completes or errs.

Returns the number of bytes read.

Lua conventions on index starting at 1 are ignored. Indexes here are OS-mandated and start at 0.

write_some_at(self, offset: integer, buffer: byte_span) → integer

Write data to the file at the specified and blocks current fiber until it completes or errs.

Returns the number of bytes written.

Lua conventions on index starting at 1 are ignored. Indexes here are OS-mandated and start at 0.

Properties

is_open: boolean

Whether the file is open.

size: integer

The size of the file.