diff --git a/dirent.c b/dirent.c
index ae576c82..de5a163d 100644
--- a/dirent.c
+++ b/dirent.c
@@ -83,9 +83,12 @@ SYS_FUNC(getdents)
 		tprints(", ");
 		return 0;
 	}
+
+	const unsigned int count = tcp->u_arg[2];
+
 	if (syserror(tcp) || !verbose(tcp)) {
 		printaddr(tcp->u_arg[1]);
-		tprintf(", %lu", tcp->u_arg[2]);
+		tprintf(", %u", count);
 		return 0;
 	}
 
@@ -101,7 +104,7 @@ SYS_FUNC(getdents)
 		buf = malloc(len);
 		if (!buf || umoven(tcp, tcp->u_arg[1], len, buf) < 0) {
 			printaddr(tcp->u_arg[1]);
-			tprintf(", %lu", tcp->u_arg[2]);
+			tprintf(", %u", count);
 			free(buf);
 			return 0;
 		}
@@ -150,7 +153,7 @@ SYS_FUNC(getdents)
 		tprints("]");
 	else
 		tprintf("/* %u entries */", dents);
-	tprintf(", %lu", tcp->u_arg[2]);
+	tprintf(", %u", count);
 	free(buf);
 	return 0;
 }
diff --git a/dirent64.c b/dirent64.c
index 3c90a258..448a2f1a 100644
--- a/dirent64.c
+++ b/dirent64.c
@@ -49,9 +49,12 @@ SYS_FUNC(getdents64)
 		tprints(", ");
 		return 0;
 	}
+
+	const unsigned int count = tcp->u_arg[2];
+
 	if (syserror(tcp) || !verbose(tcp)) {
 		printaddr(tcp->u_arg[1]);
-		tprintf(", %lu", tcp->u_arg[2]);
+		tprintf(", %u", count);
 		return 0;
 	}
 
@@ -67,7 +70,7 @@ SYS_FUNC(getdents64)
 		buf = malloc(len);
 		if (!buf || umoven(tcp, tcp->u_arg[1], len, buf) < 0) {
 			printaddr(tcp->u_arg[1]);
-			tprintf(", %lu", tcp->u_arg[2]);
+			tprintf(", %u", count);
 			free(buf);
 			return 0;
 		}
@@ -117,7 +120,7 @@ SYS_FUNC(getdents64)
 		tprints("]");
 	else
 		tprintf("/* %u entries */", dents);
-	tprintf(", %lu", tcp->u_arg[2]);
+	tprintf(", %u", count);
 	free(buf);
 	return 0;
 }
diff --git a/tests/getdents.c b/tests/getdents.c
index 16541df6..7ea2067f 100644
--- a/tests/getdents.c
+++ b/tests/getdents.c
@@ -96,7 +96,6 @@ int
 main(int ac, const char **av)
 {
 	char *dname;
-	int rc;
 
 	assert(ac == 1);
 	assert(asprintf(&dname, "%s.test.tmp.dir", av[0]) > 0);
@@ -106,9 +105,16 @@ main(int ac, const char **av)
 	assert(!creat(fname, 0600));
 	assert(!close(0));
 	assert(!open(".", O_RDONLY | O_DIRECTORY));
-	while ((rc = syscall(__NR_getdents, 0, buf, sizeof(buf)))) {
+
+	unsigned long count = (unsigned long) 0xfacefeeddeadbeef;
+	long rc = syscall(__NR_getdents, (long) 0xdefacedffffffff, NULL, count);
+	printf("getdents(-1, NULL, %u) = %ld %s (%m)\n",
+	       (unsigned) count, rc, errno2name());
+
+	count = (unsigned long) 0xfacefeed00000000 | sizeof(buf);
+	while ((rc = syscall(__NR_getdents, 0, buf, count))) {
 		kernel_dirent *d;
-		int i;
+		long i;
 
 		if (rc < 0)
 			perror_msg_and_skip("getdents");
@@ -119,9 +125,9 @@ main(int ac, const char **av)
 				printf(", ");
 			print_dirent(d);
 		}
-		printf("], %zu) = %d\n", sizeof(buf), rc);
+		printf("], %u) = %ld\n", (unsigned) count, rc);
 	}
-	printf("getdents(0, [], %zu) = 0\n", sizeof(buf));
+	printf("getdents(0, [], %u) = 0\n", (unsigned) count);
 	puts("+++ exited with 0 +++");
 	assert(!unlink(fname));
 	assert(!chdir(".."));
diff --git a/tests/getdents64.c b/tests/getdents64.c
index 7077d9c7..54149d21 100644
--- a/tests/getdents64.c
+++ b/tests/getdents64.c
@@ -101,7 +101,6 @@ int
 main(int ac, const char **av)
 {
 	char *dname;
-	int rc;
 
 	assert(ac == 1);
 	assert(asprintf(&dname, "%s.test.tmp.dir", av[0]) > 0);
@@ -111,9 +110,16 @@ main(int ac, const char **av)
 	assert(!creat(fname, 0600));
 	assert(!close(0));
 	assert(!open(".", O_RDONLY | O_DIRECTORY));
-	while ((rc = syscall(__NR_getdents64, 0, buf, sizeof(buf)))) {
+
+	unsigned long count = (unsigned long) 0xfacefeeddeadbeef;
+	long rc = syscall(__NR_getdents64, (long) 0xdefacedffffffff, NULL, count);
+	printf("getdents64(-1, NULL, %u) = %ld %s (%m)\n",
+	       (unsigned) count, rc, errno2name());
+
+	count = (unsigned long) 0xfacefeed00000000 | sizeof(buf);
+	while ((rc = syscall(__NR_getdents64, 0, buf, count))) {
 		kernel_dirent64 *d;
-		int i;
+		long i;
 
 		if (rc < 0)
 			perror_msg_and_skip("getdents64");
@@ -124,9 +130,9 @@ main(int ac, const char **av)
 				printf(", ");
 			print_dirent(d);
 		}
-		printf("], %zu) = %d\n", sizeof(buf), rc);
+		printf("], %u) = %ld\n", (unsigned) count, rc);
 	}
-	printf("getdents64(0, [], %zu) = 0\n", sizeof(buf));
+	printf("getdents64(0, [], %u) = 0\n", (unsigned) count);
 	puts("+++ exited with 0 +++");
 	assert(!unlink(fname));
 	assert(!chdir(".."));