diff --git a/ObsoleteFiles.inc b/ObsoleteFiles.inc
index e7d62afdd76..50f426085ef 100644
--- a/ObsoleteFiles.inc
+++ b/ObsoleteFiles.inc
@@ -51,6 +51,9 @@
 #   xargs -n1 | sort | uniq -d;
 # done
 
+# 20240414: unix_socketpair_test renamed
+OLD_FILES+=usr/tests/sys/kern/unix_socketpair_test
+
 # 20240406: new clang import which bumps version from 17 to 18
 OLD_FILES+=usr/lib/clang/17/include/__clang_cuda_builtin_vars.h
 OLD_FILES+=usr/lib/clang/17/include/__clang_cuda_cmath.h
diff --git a/tests/sys/kern/Makefile b/tests/sys/kern/Makefile
index bc42f53a284..c5107ce8f9f 100644
--- a/tests/sys/kern/Makefile
+++ b/tests/sys/kern/Makefile
@@ -50,7 +50,7 @@ ATF_TESTS_C+=	unix_passfd_stream
 TEST_METADATA.unix_passfd_stream+=	is_exclusive="true"
 ATF_TESTS_C+=	unix_seqpacket_test
 TEST_METADATA.unix_seqpacket_test+=	timeout="15"
-ATF_TESTS_C+=	unix_socketpair_test
+ATF_TESTS_C+=	unix_stream
 ATF_TESTS_C+=	waitpid_nohang
 ATF_TESTS_C+=	pdeathsig
 ATF_TESTS_C+=	sigsys
diff --git a/tests/sys/kern/unix_socketpair_test.c b/tests/sys/kern/unix_stream.c
similarity index 83%
rename from tests/sys/kern/unix_socketpair_test.c
rename to tests/sys/kern/unix_stream.c
index b994b791a2e..d57cfad020f 100644
--- a/tests/sys/kern/unix_socketpair_test.c
+++ b/tests/sys/kern/unix_stream.c
@@ -37,23 +37,30 @@
 
 #include <atf-c.h>
 
+static void
+do_socketpair(int *sv)
+{
+	int s;
+
+	s = socketpair(PF_LOCAL, SOCK_STREAM, 0, sv);
+	ATF_REQUIRE_EQ(0, s);
+	ATF_REQUIRE(sv[0] >= 0);
+	ATF_REQUIRE(sv[1] >= 0);
+	ATF_REQUIRE(sv[0] != sv[1]);
+}
+
 /* getpeereid(3) should work with stream sockets created via socketpair(2) */
 ATF_TC_WITHOUT_HEAD(getpeereid);
 ATF_TC_BODY(getpeereid, tc)
 {
 	int sv[2];
-	int s;
 	uid_t real_euid, euid;
 	gid_t real_egid, egid;
 
 	real_euid = geteuid();
 	real_egid = getegid();
 
-	s = socketpair(PF_LOCAL, SOCK_STREAM, 0, sv);
-	ATF_CHECK_EQ(0, s);
-	ATF_CHECK(sv[0] >= 0);
-	ATF_CHECK(sv[1] >= 0);
-	ATF_CHECK(sv[0] != sv[1]);
+	do_socketpair(sv);
 
 	ATF_REQUIRE_EQ(0, getpeereid(sv[0], &euid, &egid));
 	ATF_CHECK_EQ(real_euid, euid);
@@ -67,10 +74,23 @@ ATF_TC_BODY(getpeereid, tc)
 	close(sv[1]);
 }
 
+/* Sending zero bytes should succeed (once regressed in aba79b0f4a3f). */
+ATF_TC_WITHOUT_HEAD(send_0);
+ATF_TC_BODY(send_0, tc)
+{
+	int sv[2];
+
+	do_socketpair(sv);
+	ATF_REQUIRE(send(sv[0], sv, 0, 0) == 0);
+	close(sv[0]);
+	close(sv[1]);
+}
+
 
 ATF_TP_ADD_TCS(tp)
 {
 	ATF_TP_ADD_TC(tp, getpeereid);
+	ATF_TP_ADD_TC(tp, send_0);
 
 	return atf_no_error();
 }