About making dock window.

[Magicloud Magiclouds <magicloud magiclouds gmail com>]

Hi,
  I am working on make some dock windows. After I set type_hint and
_NET_WM_STRUT, it worked. But I do not know how to deal with another
dock program.
  I.e., I am making one for left edge of screen, and there already
exists one for top edge of screen. Is there a way for my window to
know that there is another dock window might overlap, so my window has
to give some space on top side to avoid the other dock?

Thanks.
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