Linux Inotify implementation

auto i=x::inotify::create();

    w=i->create(".", x::inotify_create | x::inotify_delete,
                (uint32_t mask, uint32_t cookie, const char *name)
                    // Do something


The inotify(7) API is a mechanism for applications to monitor the contents of a directory or a file, and be notified when it changes. The x::inotify handle is a file descriptor handle. A single x::inotify handle may be used to monitor multiple files or directories.

x::inotify handle's create() method begins monitoring a new directory or a file. Its first parameter specifies the directory or the file to monitor.

The second parameter is a set of one or more flags: x::inotify_access, x::inotify_attrib, x::inotify_close, x::inotify_close_nowrite, x::inotify_close_write, x::inotify_create, x::inotify_delete, x::inotify_delete_self, x::inotify_dont_follow, x::inotify_excl_unlink, x::inotify_modify, x::inotify_move, x::inotify_move_self, x::inotify_moved_from, x::inotify_moved_to, and x::inotify_open; this selects which events to report.

The third parameter is a lambda that gets invoked when the selected event occured. The first parameter is one of the events that have occured; additionally x::inotify_ignored, x::inotify_isdir, or x::inotify_unmount could be reported too. The second parameter is an event cookie (this is used mostly to link together the x::inotify_moved_from and x::inotify_moved_to events. The third parameter is the file or the directory pathname whose event is reported.

create() return a mcguffin handle for the events being monitored. x::inotify's read() reads one or more events from the underlying file descriptors, and invokes the appropriate lambdas. There is no explicit call to stop monitoring, when the last reference to the mcguffin handle goes out of scope, and it gets destroyed, the monitoring stops automatically.

The x::inotify handle is a blocking file descriptor by default. Use nonblock() to put the inotify handle into non-blocking mode.