BWFM_NFILETYPES
for (i = 0; i < BWFM_NFILETYPES; i++) {
for (int i = 0; i < BWFM_NFILETYPES; i++) {
KASSERT(which < BWFM_NFILETYPES);
} ctx_file[BWFM_NFILETYPES];