ok $? "$what: nothing is printed on stdout"
# Check for expected error string in stderr.
- grep --quiet --fixed-strings -e "$expected_error_str" "$tmp_stderr"
+ bt_grep --quiet --fixed-strings -e "$expected_error_str" "$tmp_stderr"
local status=$?
ok "$status" "$what: expected error message"
if [ "$status" -ne 0 ]; then