FileDescriptor Class Reference


                    
                    
                    handle

File descriptor handle.

Declaration

Swift

public private(set) var handle: Handle


                    
                    
                    Handle

File descriptor handle.

Declaration

Swift

public typealias Handle = Int32


                    
                    
                    standardInput

Standard input file descriptor

Declaration

Swift

public static var standardInput = try! FileDescriptor(STDIN_FILENO)


                    
                    
                    standardOutput

Standard output file descriptor

Declaration

Swift

public static var standardOutput = try! FileDescriptor(STDOUT_FILENO)


                    
                    
                    standardError

Standard error file descriptor

Declaration

Swift

public static var standardError = try! FileDescriptor(STDERR_FILENO)


                    
                    
                    init(_:)

Creates a FileDescriptor from a file descriptor handle.

Warning

This operation will configure the file descriptor as non-blocking.

Throws

The following errors might be thrown:

VeniceError.invalidFileDescriptor

Thrown when the operation is performed on an invalid file descriptor.

Declaration

Swift

public init(_ handle: Handle) throws

Parameters


                                fileDescriptor

Previously opened file descriptor.


                    
                    
                    read(_:deadline:)

Reads from the file descriptor.

Throws

The following errors might be thrown:

VeniceError.readFailed

Thrown when read operation fails.

VeniceError.invalidFileDescriptor

Thrown when handle is not an open file descriptor.

Declaration

Swift

public func read(
        _ buffer: UnsafeMutableRawBufferPointer,
        deadline: Deadline
    ) throws -> UnsafeRawBufferPointer

Parameters

`buffer`	Buffer in which the data will be read to.
`deadline`	`deadline` is a point in time when the operation should timeout. Use the `.fromNow()` function to get the current point in time. Use `.immediate` if the operation needs to be performed without blocking. Use `.never` to allow the operation to block forever if needed.

Return Value

Buffer containing the amount of bytes read.


                    
                    
                    write(_:deadline:)

Writes to the file descriptor.

Throws

The following errors might be thrown:

VeniceError.writeFailed

Thrown when write operation fails.

VeniceError.invalidFileDescriptor

Thrown when handle is not an open file descriptor.

Declaration

Swift

public func write(_ buffer: UnsafeRawBufferPointer, deadline: Deadline) throws

Parameters

`buffer`	Buffer which will be written to the file descriptor.
`deadline`	`deadline` is a point in time when the operation should timeout. Use the `.fromNow()` function to get the current point in time. Use `.immediate` if the operation needs to be performed without blocking. Use `.never` to allow the operation to block forever if needed.


                    
                    
                    close()

Closes a file descriptor, so that it no longer refers to any file and may be reused. Any record locks held on the file it was associated with, and owned by the process, are removed (regardless of the file descriptor that was used to obtain the lock).

Warning

If handle is the last file descriptor referring to the underlying open file description, the resources associated with the open file description are freed; if the file descriptor was the last reference to a file which has been removed using unlink, the file is deleted.

Throws

The following errors might be thrown:

VeniceError.invalidFileDescriptor

Thrown when handle is not an open file descriptor.

Declaration

Swift

public func close() throws


                    
                    
                    detach()

Detaches the underlying handle. After detach any operation on the FileDescriptor will throw an error.

Declaration

Swift

@discardableResult public func detach() throws -> Handle

Return Value

The underlying file descriptor.


                    
                    
                    poll(_:event:deadline:)

Waits for the file descriptor to become either readable/writable or to get into an error state. Either case leads to a successful return from the function. To distinguish the two outcomes, follow up with a read/write operation on the file descriptor.

Throws

The following errors might be thrown:

VeniceError.invalidFileDescriptor

Thrown when the operation is performed on an invalid file descriptor.

VeniceError.canceledCoroutine

Thrown when the operation is performed within a canceled coroutine.

VeniceError.fileDescriptorBlockedInAnotherCoroutine

Thrown when another coroutine is already blocked on poll with this file descriptor.

VeniceError.deadlineReached

Thrown when the operation reaches the deadline.

Declaration

Swift

public static func poll(_ handle: Handle, event: PollEvent, deadline: Deadline) throws

Parameters

`event`	Use `.read` to wait for the file descriptor to become readable. Use `.write` to wait for the file descriptor to become writable.
`deadline`	`deadline` is a point in time when the operation should timeout. Use the `.fromNow()` function to get the current point in time. Use `.immediate` if the operation needs to be performed without blocking. Use `.never` to allow the operation to block forever if needed.


                    
                    
                    clean(_:)

Erases cached info about a file descriptor.

This function drops any state that Venice associates with the file descriptor.

Warning

clean has to be called with file descriptors provided by third-party libraries, just before returning them back to their original owners. Otherwise the behavior is undefined.

Declaration

Swift

public static func clean(_ handle: Handle)


                    
                    
                    PollEvent

Event used to poll file descriptors for reading or writing.

Declaration

Swift

public enum PollEvent