File

A simple OS file wrapper which can return file descriptors for read/write/events.

.new `(path, mode)`

Create a new file with the given mode. Mode values are:

Read	prepare file for reading
Write	prepare file for writing
Events	listen to file changes

:readLine `()`

Read a line. Returns a string or nil on EOF.

:write `(str)`

Write a string to a file.

Events

:events `(flags)`

Listen for OS notifications on file changes. The flags determine which notifications are watched. You can combine flags by adding them. The function returns the notified event as a number.

DeleteEvent	Vnode was removed.
WriteEvent	Data contents changed.
ExtendEvent	Size increased.
AttribEvent	Attributes changed.
LinkEvent	Link count changed.
RenameEvent	Vnode was renamed.
RevokeEvent	Vnode access was revoked.
NoneEvent	No specific vnode event: to test for EVFILT_READ activation.

Usage example:

local lens = require 'lens'
local File = lens.File
local DELETE, WRITE = File.DeleteEvent, File.WriteEvent
f = lens.File('foo.lua', File.Events)
while true do
  local ev = f:events(DELETE + WRITE)
  if ev == DELETE then
    print(f.path, 'deleted')
    break
  else
    print(f.path, File.EventName[ev])
  end
end

.eventMap

Translate an event number to a table with keys representing active flags.

Lubyk documentation

File

.new (path, mode)

:readLine ()