CHN_F_RUNNING
#define CHN_F_MMAP_INVALID (CHN_F_DEAD | CHN_F_RUNNING)
rdch->flags &= ~(CHN_F_RUNNING | CHN_F_MMAP |
wrch->flags &= ~(CHN_F_RUNNING | CHN_F_MMAP |
} else if (!(ch->flags & CHN_F_RUNNING))
ch->flags |= CHN_F_RUNNING;