fs2-io/fs2.io.file/FileHandle

FileHandle

trait FileHandle[F <: ([_$1] =>> Any)]
Provides the ability to read/write/lock/inspect a file in the effect F.
Companion
object
class Object
trait Matchable
class Any

Type members

Types

type Lock
Opaque type representing an exclusive lock on a file.

Value members

Methods

def force(metaData: Boolean): F[Unit]
Force any updates for the underlying file to storage.
Value Params
metaData
If true, also attempts to force file metadata updates to storage.
def lock: F[Lock]
Acquire an exclusive lock on the underlying file.
Returns
a lock object which can be used to unlock the file.
def lock(position: Long, size: Long, shared: Boolean): F[Lock]
Acquire a lock on the specified region of the underlying file.
Value Params
position
the start of the region to lock.
shared
to request a shared lock across process boundaries (may be converted to an exclusive lock on some operating systems).
size
the size of the region to lock.
Returns
a lock object which can be used to unlock the region.
def read(numBytes: Int, offset: Long): F[Option[Chunk[Byte]]]
Read the specified number of bytes at a particular offset.
Value Params
numBytes
the number of bytes to read.
offset
the offset from the start of the file.
Returns
a number of bytes from the file (at most, numBytes in size).
def size: F[Long]
Report the current size of the file.
Returns
the size of the file.
def truncate(size: Long): F[Unit]
Truncate the underlying file to the specified size.
Value Params
size
the size of the file after truncation.
def tryLock: F[Option[Lock]]
Attempt to acquire an exclusive lock on the underlying file.
Returns
if the lock could be acquired, a lock object which can be used to unlock the file.
def tryLock(position: Long, size: Long, shared: Boolean): F[Option[Lock]]
Attempt to acquire a lock on the specified region of the underlying file.
Value Params
position
the start of the region to lock.
shared
to request a shared lock across process boundaries (may be converted to an exclusive lock on some operating systems).
size
the size of the region to lock.
Returns
if the lock could be acquired, a lock object which can be used to unlock the region.
def unlock(lock: Lock): F[Unit]
Unlock the (exclusive or regional) lock represented by the supplied Lock.
Value Params
lock
the lock object which represents the locked file or region.
def write(bytes: Chunk[Byte], offset: Long): F[Int]
Write the specified bytes at a particular offset.
Value Params
bytes
the bytes to write to the FileHandle.
offset
the offset at which to write the bytes.
Returns
the number of bytes written.