def initialize(notifier, path, *flags, &callback)
@notifier = notifier
@callback = callback || proc {}
@path = path
@flags = flags.freeze
@id = Native.inotify_add_watch(@notifier.fd, path.dup,
Native::Flags.to_mask(flags))
unless @id < 0
@notifier.watchers[@id] = self
return
end
raise SystemCallError.new(
"Failed to watch #{path.inspect}" +
case FFI.errno
when Errno::EACCES::Errno; ": read access to the given file is not permitted."
when Errno::EBADF::Errno; ": the given file descriptor is not valid."
when Errno::EFAULT::Errno; ": path points outside of the process's accessible address space."
when Errno::EINVAL::Errno; ": the given event mask contains no legal events; or fd is not an inotify file descriptor."
when Errno::ENOMEM::Errno; ": insufficient kernel memory was available."
when Errno::ENOSPC::Errno; ": The user limit on the total number of inotify watches was reached or the kernel failed to allocate a needed resource."
else; ""
end,
FFI.errno)
end