engine::io::FdPoller Class Reference

Table of Contents

• Public Types
• Public Member Functions
• Detailed Description
• Member Enumeration Documentation
• Kind
• Member Function Documentation
• Invalidate()
• Reset()
• Wait()

Low-level poller that can wait for read, write, and read/write operations on a file descriptor. It does not provide read/write operations. More...

#include <userver/engine/io/fd_poller.hpp>

Public Types
enum class	Kind {   kRead = 1 ,   kWrite = 2 ,   kReadWrite = 3 }
	Operation kind to wait for. More...

Public Member Functions
	FdPoller (const FdPoller &)=delete
	FdPoller (FdPoller &&)=delete
FdPoller &	operator= (const FdPoller &)=delete
FdPoller &	operator= (FdPoller &&)=delete
	operator bool () const noexcept
	The same as IsValid().
bool	IsValid () const noexcept
	Whether the file descriptor is valid.
int	GetFd () const
	If IsValid(), get file descriptor.
void	Invalidate ()
void	Reset (int fd, Kind kind)
std::optional< Kind >	Wait (Deadline)

Detailed Description

Low-level poller that can wait for read, write, and read/write operations on a file descriptor. It does not provide read/write operations.

Note

FdPoller is not thread safe and its methods must not be called from multiple threads simultaneously.

Definition at line 24 of file fd_poller.hpp.

Member Enumeration Documentation

Kind

enum class engine::io::FdPoller::Kind

strong

Operation kind to wait for.

Enumerator
kWrite	< wait for read availability
kReadWrite	< wait for write availability

Definition at line 27 of file fd_poller.hpp.

Member Function Documentation

Invalidate()

void engine::io::FdPoller::Invalidate

(

)

When you're done with fd, call Invalidate(). It unregisters the fd, after that you have to call close(2) by yourself. After Invalidate() you may not call Wait().

Reset()

void engine::io::FdPoller::Reset	(	int	fd,
		Kind	kind
	)

Setup fd and kind to wait for. After Reset() you may call Wait(). FdPoller does not take the ownership of fd, you still have to close fd when you're done.

Wait()

std::optional< Kind > engine::io::FdPoller::Wait

(

Deadline

)

Wait for an event kind that was passed in the latest Reset() call. If the operation (read/write) can already be handled, Wait() returns immediately. You have to call Reset() at least once before call to Wait().

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The documentation for this class was generated from the following file:

• userver/engine/io/fd_poller.hpp