WS_KERNEL_BG
sc->sc_kernattr = (WS_KERNEL_FG << 24) | (WS_KERNEL_BG << 16);
# if defined(WS_KERNEL_FG) || defined(WS_KERNEL_BG) || \
# if !defined(WS_KERNEL_BG)
#if defined(WS_KERNEL_FG) || defined(WS_KERNEL_BG) || \
#ifndef WS_KERNEL_BG
WS_KERNEL_FG, WS_KERNEL_BG,
vd->msgattrs.kernel_bg = WS_KERNEL_BG;