require 'ffi' module Inotify extend FFI::Library ffi_lib FFI::Library::LIBC class Event < FFI::Struct layout \ :wd, :int, :mask, :uint, :cookie, :uint, :len, :uint end attach_function :init, :inotify_init, [ ], :int attach_function :add_watch, :inotify_add_watch, [ :int, :string, :uint ], :int attach_function :rm_watch, :inotify_rm_watch, [ :int, :uint ], :int attach_function :read, [ :int, :buffer_out, :uint ], :int IN_ACCESS=0x00000001 IN_MODIFY=0x00000002 IN_ATTRIB=0x00000004 IN_CLOSE_WRITE=0x00000008 IN_CLOSE_NOWRITE=0x00000010 IN_CLOSE=(IN_CLOSE_WRITE | IN_CLOSE_NOWRITE) IN_OPEN=0x00000020 IN_MOVED_FROM=0x00000040 IN_MOVED_TO=0x00000080 IN_MOVE= (IN_MOVED_FROM | IN_MOVED_TO) IN_CREATE=0x00000100 IN_DELETE=0x00000200 IN_DELETE_SELF=0x00000400 IN_MOVE_SELF=0x00000800 # Events sent by the kernel. IN_UNMOUNT=0x00002000 IN_Q_OVERFLOW=0x00004000 IN_IGNORED=0x00008000 IN_ONLYDIR=0x01000000 IN_DONT_FOLLOW=0x02000000 IN_MASK_ADD=0x20000000 IN_ISDIR=0x40000000 IN_ONESHOT=0x80000000 IN_ALL_EVENTS=(IN_ACCESS | IN_MODIFY | IN_ATTRIB | IN_CLOSE_WRITE \ | IN_CLOSE_NOWRITE | IN_OPEN | IN_MOVED_FROM \ | IN_MOVED_TO | IN_CREATE | IN_DELETE \ | IN_DELETE_SELF | IN_MOVE_SELF) end if $0 == __FILE__ fd = Inotify.init puts "fd=#{fd}" wd = Inotify.add_watch(fd, "/tmp/", Inotify::IN_ALL_EVENTS) fp = FFI::IO.for_fd(fd) puts "wfp=#{fp}" while true buf = FFI::Buffer.alloc_out(Inotify::Event.size + 4096, 1, false) ev = Inotify::Event.new buf ready = IO.select([ fp ], nil, nil, nil) n = Inotify.read(fd, buf, buf.total) puts "Read #{n} bytes from inotify fd" puts "event.wd=#{ev[:wd]} mask=#{ev[:mask]} len=#{ev[:len]} name=#{ev[:len] > 0 ? buf.get_string(16) : 'unknown'}" end end