Specify the window name and group (or class).
This function is only available under X. It lets you to specify the
window name and group (or class). They are important because they allow
the window manager to remember the window attributes (position, layer,
etc). Note that the name and the title of the window are two different
things: the title is what appears in the title bar of the window, but
usually has no other effects on the behaviour of the application.
The following projects include source code containing this keyword: