checkf
static FILE *checkf(register char *fs, int *clearfirst);
if ((f = checkf (fnames[fnum], &clearit)) != NULL) {
if ((in_file = checkf(fnames[fnum])) == NULL) {
static FILE *checkf(char *);
checkf(longname, (stbuf.st_mode & S_IFMT) == S_IFDIR, Fflag) == 0)
if (checkf(namep, is_directory(namep), Fflag) == 0) {
if (checkf(namep, is_directory(namep), Fflag) == 0) {
static int checkf(char *name, int mode, int howmuch);