Accessing system resources through a web page

Is it possible to access system resources via a web page?

Specifically I would be interested in accessing system calls in ord开发者_高级运维er to put the computer into standby or sleep.

At this point, I am language-independent. I would imagine that some sort of special access would need to be granted before anything of this nature occurs. My searches haven't really returned much help, so any suggestions would be great.

Yes, it is possible. See for example the online antiviruses.

I haven't done such thing but java applets can achieve that, also some kind of ActiveX controls. Of course user permission is required.