System.FS.API.Lazy

API

module System.FS.API

Lazy functions

hGetAll :: Monad m => HasFS m h -> Handle h -> m ByteString

Read all the data from the given file handle 64kB at a time.

Stops when EOF is reached.

hGetAllAt

Arguments

:: Monad m

=> HasFS m h

-> Handle h

-> AbsOffset

The offset at which to read.

-> m ByteString

Like hGetAll, but is thread safe since it does not change or depend on the file offset. pread syscall is used internally.

hGetExactly :: forall m h. (HasCallStack, MonadThrow m) => HasFS m h -> Handle h -> Word64 -> m ByteString

Makes sure it reads all requested bytes. If eof is found before all bytes are read, it throws an exception.

hGetExactlyAt

Arguments

:: forall m h. (HasCallStack, MonadThrow m)

=> HasFS m h

-> Handle h

-> Word64

The number of bytes to read.

-> AbsOffset

The offset at which to read.

-> m ByteString

Like hGetExactly, but is thread safe since it does not change or depend on the file offset. pread syscall is used internally.

hPut :: forall m h. (HasCallStack, Monad m) => HasFS m h -> Handle h -> Builder -> m Word64

This function makes sure that the whole Builder is written.

The chunk size of the resulting ByteString determines how much memory will be used while writing to the handle.

hPutAll :: forall m h. (HasCallStack, Monad m) => HasFS m h -> Handle h -> ByteString -> m Word64

This function makes sure that the whole ByteString is written.