Index: head/usr.bin/grep/tests/grep_freebsd_test.sh
===================================================================
--- head/usr.bin/grep/tests/grep_freebsd_test.sh	(revision 317299)
+++ head/usr.bin/grep/tests/grep_freebsd_test.sh	(revision 317300)
@@ -1,55 +1,89 @@
 #
 # Copyright (c) 2017 Kyle Evans <kevans91@ksu.edu>
 # All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions
 # are met:
 # 1. Redistributions of source code must retain the above copyright
 #    notice, this list of conditions and the following disclaimer.
 # 2. Redistributions in binary form must reproduce the above copyright
 #    notice, this list of conditions and the following disclaimer in the
 #    documentation and/or other materials provided with the distribution.
 #
 # THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 # ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 # TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 # PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
 # BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 # CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 # SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 # INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 # CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 # ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 # POSSIBILITY OF SUCH DAMAGE.
 #
 # $FreeBSD$
 
+# What grep(1) are we working with?
+# - 0 : bsdgrep
+# - 1 : gnu grep 2.51 (base)
+# - 2 : gnu grep (ports)
+GREP_TYPE_BSD=0
+GREP_TYPE_GNU_FREEBSD=1
+GREP_TYPE_GNU=2
+GREP_TYPE_UNKNOWN=3
+
+grep_type()
+{
+	local grep_version=$(grep --version)
+
+	case "$grep_version" in
+	*"BSD grep"*)
+		return $GREP_TYPE_BSD
+		;;
+	*"GNU grep"*)
+		case "$grep_version" in
+		*2.5.1-FreeBSD*)
+			return $GREP_TYPE_GNU_FREEBSD
+			;;
+		*)
+			return $GREP_TYPE_GNU
+			;;
+		esac
+		;;
+	esac
+	atf_fail "unknown grep type: $grep_version"
+}
+
 atf_test_case grep_r_implied
 grep_r_implied_body()
 {
-	(cd "$(atf_get_srcdir)" && grep -r -e "test" < /dev/null) ||
-	    atf_skip "Implied working directory is not supported with your version of grep(1)"
+	grep_type
+	if [ $? -ne $GREP_TYPE_BSD ]; then
+		atf_skip "this test only works with bsdgrep(1)"
+	fi
+
 	(cd "$(atf_get_srcdir)" && grep -r --exclude="*.out" -e "test" .) > d_grep_r_implied.out
 
 	atf_check -s exit:0 -x \
 	    "(cd $(atf_get_srcdir) && grep -r --exclude=\"*.out\" -e \"test\") | diff d_grep_r_implied.out -"
 }
 
 atf_test_case rgrep
 rgrep_head()
 {
 	atf_set "require.progs" "rgrep"
 }
 rgrep_body()
 {
 	grep -r --exclude="*.out" -e "test" "$(atf_get_srcdir)" > d_grep_r_implied.out
 
 	atf_check -o file:d_grep_r_implied.out rgrep --exclude="*.out" -e "test" "$(atf_get_srcdir)"
 }
 
 atf_init_test_cases()
 {
 	atf_add_test_case grep_r_implied
 	atf_add_test_case rgrep
 }