PUFFSDEV_NONBLOCK
if (mode != PUFFSDEV_BLOCK && mode != PUFFSDEV_NONBLOCK) {
puffs_setblockingmode(pu, PUFFSDEV_NONBLOCK);
if (puffs_setblockingmode(pu, PUFFSDEV_NONBLOCK) == -1)
if (puffs_setblockingmode(pu, PUFFSDEV_NONBLOCK) == -1)