Documentation
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Overview ¶
Package poll supports non-blocking I/O on file descriptors with polling. This supports I/O operations that block only a goroutine, not a thread. This is used by the net and os packages. It uses a poller built into the runtime, with support from the runtime scheduler.
Index ¶
- Variables
- func CopyFileRange(dst, src *FD, remain int64) (written int64, handled bool, err error)
- func DupCloseOnExec(fd int) (int, string, error)
- func IsPollDescriptor(fd uintptr) bool
- func SendFile(dstFD *FD, src int, remain int64) (int64, error)
- func Splice(dst, src *FD, remain int64) (written int64, handled bool, sc string, err error)
- type DeadlineExceededError
- type FD
- func (fd *FD) Accept() (int, syscall.Sockaddr, string, error)
- func (fd *FD) Close() error
- func (fd *FD) Dup() (int, string, error)
- func (fd *FD) Fchdir() error
- func (fd *FD) Fchmod(mode uint32) error
- func (fd *FD) Fchown(uid, gid int) error
- func (fd *FD) Fstat(s *syscall.Stat_t) error
- func (fd *FD) Fsync() error
- func (fd *FD) Ftruncate(size int64) error
- func (fd *FD) Init(net string, pollable bool) error
- func (fd *FD) Pread(p []byte, off int64) (int, error)
- func (fd *FD) Pwrite(p []byte, off int64) (int, error)
- func (fd *FD) RawControl(f func(uintptr)) error
- func (fd *FD) RawRead(f func(uintptr) bool) error
- func (fd *FD) RawWrite(f func(uintptr) bool) error
- func (fd *FD) Read(p []byte) (int, error)
- func (fd *FD) ReadDirent(buf []byte) (int, error)
- func (fd *FD) ReadFrom(p []byte) (int, syscall.Sockaddr, error)
- func (fd *FD) ReadFromInet4(p []byte, from *syscall.SockaddrInet4) (int, error)
- func (fd *FD) ReadFromInet6(p []byte, from *syscall.SockaddrInet6) (int, error)
- func (fd *FD) ReadMsg(p []byte, oob []byte, flags int) (int, int, int, syscall.Sockaddr, error)
- func (fd *FD) ReadMsgInet4(p []byte, oob []byte, flags int, sa4 *syscall.SockaddrInet4) (int, int, int, error)
- func (fd *FD) ReadMsgInet6(p []byte, oob []byte, flags int, sa6 *syscall.SockaddrInet6) (int, int, int, error)
- func (fd *FD) Seek(offset int64, whence int) (int64, error)
- func (fd *FD) SetBlocking() error
- func (fd *FD) SetDeadline(t time.Time) error
- func (fd *FD) SetReadDeadline(t time.Time) error
- func (fd *FD) SetWriteDeadline(t time.Time) error
- func (fd *FD) SetsockoptByte(level, name int, arg byte) error
- func (fd *FD) SetsockoptIPMreq(level, name int, mreq *syscall.IPMreq) error
- func (fd *FD) SetsockoptIPMreqn(level, name int, mreq *syscall.IPMreqn) error
- func (fd *FD) SetsockoptIPv6Mreq(level, name int, mreq *syscall.IPv6Mreq) error
- func (fd *FD) SetsockoptInet4Addr(level, name int, arg [4]byte) error
- func (fd *FD) SetsockoptInt(level, name, arg int) error
- func (fd *FD) SetsockoptLinger(level, name int, l *syscall.Linger) error
- func (fd *FD) Shutdown(how int) error
- func (fd *FD) WaitWrite() error
- func (fd *FD) Write(p []byte) (int, error)
- func (fd *FD) WriteMsg(p []byte, oob []byte, sa syscall.Sockaddr) (int, int, error)
- func (fd *FD) WriteMsgInet4(p []byte, oob []byte, sa *syscall.SockaddrInet4) (int, int, error)
- func (fd *FD) WriteMsgInet6(p []byte, oob []byte, sa *syscall.SockaddrInet6) (int, int, error)
- func (fd *FD) WriteOnce(p []byte) (int, error)
- func (fd *FD) WriteTo(p []byte, sa syscall.Sockaddr) (int, error)
- func (fd *FD) WriteToInet4(p []byte, sa *syscall.SockaddrInet4) (int, error)
- func (fd *FD) WriteToInet6(p []byte, sa *syscall.SockaddrInet6) (int, error)
- func (fd *FD) Writev(v *[][]byte) (int64, error)
Constants ¶
This section is empty.
Variables ¶
Accept4Func is used to hook the accept4 call.
AcceptFunc is used to hook the accept call.
var CloseFunc func(int) error = syscall.Close
CloseFunc is used to hook the close call.
var ErrDeadlineExceeded error = &DeadlineExceededError{}
ErrDeadlineExceeded is returned for an expired deadline. This is exported by the os package as os.ErrDeadlineExceeded.
var ErrFileClosing = errors.New("use of closed file")
ErrFileClosing is returned when a file descriptor is used after it has been closed.
var ErrNetClosing = errNetClosing{}
ErrNetClosing is returned when a network descriptor is used after it has been closed.
var ErrNoDeadline = errors.New("file type does not support deadline")
ErrNoDeadline is returned when a request is made to set a deadline on a file type that does not use the poller.
var ErrNotPollable = errors.New("not pollable")
ErrNotPollable is returned when the file or socket is not suitable for event notification.
var TestHookDidWritev = func(wrote int) {}
TestHookDidWritev is a hook for testing writev.
Functions ¶
func CopyFileRange ¶
CopyFileRange copies at most remain bytes of data from src to dst, using the copy_file_range system call. dst and src must refer to regular files.
func DupCloseOnExec ¶
DupCloseOnExec dups fd and marks it close-on-exec.
func IsPollDescriptor ¶
IsPollDescriptor reports whether fd is the descriptor being used by the poller. This is only used for testing.
func Splice ¶
Splice transfers at most remain bytes of data from src to dst, using the splice system call to minimize copies of data from and to userspace.
Splice gets a pipe buffer from the pool or creates a new one if needed, to serve as a buffer for the data transfer. src and dst must both be stream-oriented sockets.
If err != nil, sc is the system call which caused the error.
Types ¶
type DeadlineExceededError ¶
type DeadlineExceededError struct{}
DeadlineExceededError is returned for an expired deadline.
func (*DeadlineExceededError) Error ¶
func (e *DeadlineExceededError) Error() string
Implement the net.Error interface. The string is "i/o timeout" because that is what was returned by earlier Go versions. Changing it may break programs that match on error strings.
func (*DeadlineExceededError) Temporary ¶
func (e *DeadlineExceededError) Temporary() bool
func (*DeadlineExceededError) Timeout ¶
func (e *DeadlineExceededError) Timeout() bool
type FD ¶
type FD struct {
// System file descriptor. Immutable until Close.
Sysfd int
// Whether this is a streaming descriptor, as opposed to a
// packet-based descriptor like a UDP socket. Immutable.
IsStream bool
// Whether a zero byte read indicates EOF. This is false for a
// message based socket connection.
ZeroReadIsEOF bool
// contains filtered or unexported fields
}
FD is a file descriptor. The net and os packages use this type as a field of a larger type representing a network connection or OS file.
func (*FD) Close ¶
Close closes the FD. The underlying file descriptor is closed by the destroy method when there are no remaining references.
func (*FD) Init ¶
Init initializes the FD. The Sysfd field should already be set. This can be called multiple times on a single FD. The net argument is a network name from the net package (e.g., "tcp"), or "file". Set pollable to true if fd should be managed by runtime netpoll.
func (*FD) RawControl ¶
RawControl invokes the user-defined function f for a non-IO operation.
func (*FD) ReadDirent ¶
ReadDirent wraps syscall.ReadDirent. We treat this like an ordinary system call rather than a call that tries to fill the buffer.
func (*FD) ReadFromInet4 ¶
ReadFromInet4 wraps the recvfrom network call for IPv4.
func (*FD) ReadFromInet6 ¶
ReadFromInet6 wraps the recvfrom network call for IPv6.
func (*FD) ReadMsgInet4 ¶
func (fd *FD) ReadMsgInet4(p []byte, oob []byte, flags int, sa4 *syscall.SockaddrInet4) (int, int, int, error)
ReadMsgInet4 is ReadMsg, but specialized for syscall.SockaddrInet4.
func (*FD) ReadMsgInet6 ¶
func (fd *FD) ReadMsgInet6(p []byte, oob []byte, flags int, sa6 *syscall.SockaddrInet6) (int, int, int, error)
ReadMsgInet6 is ReadMsg, but specialized for syscall.SockaddrInet6.
func (*FD) SetBlocking ¶
SetBlocking puts the file into blocking mode.
func (*FD) SetDeadline ¶
SetDeadline sets the read and write deadlines associated with fd.
func (*FD) SetReadDeadline ¶
SetReadDeadline sets the read deadline associated with fd.
func (*FD) SetWriteDeadline ¶
SetWriteDeadline sets the write deadline associated with fd.
func (*FD) SetsockoptByte ¶
SetsockoptByte wraps the setsockopt network call with a byte argument.
func (*FD) SetsockoptIPMreq ¶
SetsockoptIPMreq wraps the setsockopt network call with an IPMreq argument.
func (*FD) SetsockoptIPMreqn ¶
SetsockoptIPMreqn wraps the setsockopt network call with an IPMreqn argument.
func (*FD) SetsockoptIPv6Mreq ¶
SetsockoptIPv6Mreq wraps the setsockopt network call with an IPv6Mreq argument.
func (*FD) SetsockoptInet4Addr ¶
SetsockoptInet4Addr wraps the setsockopt network call with an IPv4 address.
func (*FD) SetsockoptInt ¶
SetsockoptInt wraps the setsockopt network call with an int argument.
func (*FD) SetsockoptLinger ¶
SetsockoptLinger wraps the setsockopt network call with a Linger argument.
func (*FD) WriteMsgInet4 ¶
WriteMsgInet4 is WriteMsg specialized for syscall.SockaddrInet4.
func (*FD) WriteMsgInet6 ¶
WriteMsgInet6 is WriteMsg specialized for syscall.SockaddrInet6.
func (*FD) WriteToInet4 ¶
WriteToInet4 wraps the sendto network call for IPv4 addresses.
func (*FD) WriteToInet6 ¶
WriteToInet6 wraps the sendto network call for IPv6 addresses.
Source Files
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- copy_file_range_linux.go
- errno_unix.go
- fcntl_syscall.go
- fd.go
- fd_fsync_posix.go
- fd_mutex.go
- fd_poll_runtime.go
- fd_posix.go
- fd_unix.go
- fd_writev_unix.go
- hook_cloexec.go
- hook_unix.go
- iovec_unix.go
- sendfile_linux.go
- sock_cloexec.go
- sockopt.go
- sockopt_linux.go
- sockopt_unix.go
- sockoptip.go
- splice_linux.go
- writev.go