filesize -package:basement -package:ghc -package:http-client -package:hackage-security -package:stack -package:tar -package:filemanip

For a handle hdl which attached to a physical file, hFileSize hdl returns the size of that file in 8-bit bytes.
hSetFileSize hdl size truncates the physical file with handle hdl to size bytes.
Obtain the size of a file in bytes.