get_field
char *get_field(char **, size_t *, int *);
field = get_field(line, len, &fieldlen);
ptr = get_field(line, len, &fieldlen);
for (curr_opt = get_field(options); curr_opt; curr_opt = next_opt) {
next_opt = get_field((char *) 0);
static char *get_field /* chew :-delimited field off string */