sbuf_setpos
ATF_CHECK(sbuf_setpos(sb, -1) == -1);
ATF_CHECK(sbuf_setpos(sb, 0) == 0);
ATF_CHECK(sbuf_setpos(sb, 1) == -1);
ATF_CHECK(sbuf_setpos(sb, -1) == -1);
ATF_CHECK(sbuf_setpos(sb, test_string_len + 2) == -1);
ATF_CHECK(sbuf_setpos(sb, test_string_chopped_len) == 0);
sbuf_setpos(sbuf, oldlen);
sbuf_setpos(sbuf, oldlen);
sbuf_setpos(sb, sbuf_len(sb) - 1);
sbuf_setpos(sb, sbuf_len(sb) - 1);
sbuf_setpos(sb, sbuf_len(sb) - 1);
sbuf_setpos(&sb, 0);
sbuf_setpos(sb, len);
sbuf_setpos(&sb, savedlen); \
int sbuf_setpos(struct sbuf *, ssize_t);