Node.FsNode FS API
Most fs functions let you omit the callback argument. If you do, a default callback is used that rethrows errors. To get a trace to the original call site, set the `NODE_DEBUG` environment variable.
The relative path to a filename can be used. Remember, however, that this path will be relative to process.cwd().
module Watch : sig ... endval ftruncateSync : fd -> int -> unitval fchownSync : fd -> uid:int -> gid:int -> unitval openSync : 
  path ->
  [ `Read
  | `Read_write
  | `Read_write_sync
  | `Write
  | `Write_fail_if_exists
  | `Write_read
  | `Write_read_fail_if_exists
  | `Append
  | `Append_fail_if_exists
  | `Append_read
  | `Append_read_fail_if_exists ] ->
  unitval readFileSync : string -> encoding -> stringval writeFileSync : string -> string -> encoding -> unit