CHN_REMOVE
CHN_REMOVE(d, c, channels.pcm.busy);
CHN_REMOVE(x, y, z); \
CHN_REMOVE(d, rdch, channels.pcm.opened);
CHN_REMOVE(d, wrch, channels.pcm.opened);
CHN_REMOVE(d, ch, channels.pcm);
CHN_REMOVE(p, c, children.busy);
CHN_REMOVE(parent, ch, children);
CHN_REMOVE(parent, c, children);