test68: test pipe2 functionality

Change-Id: Idb15ec83983d0b052232c9533f89d637229d19df

test/t68a.c

@@ -0,0 +1,33 @@
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+int
+main(int argc, char *argv[])
+{
+	int fd, fd_parent;
+	char buf[1];
+
+	if (argc != 2) {
+		return 1;
+	}
+
+	fd_parent = atoi(argv[1]);
+
+	/* If we open a new file, the fd we obtain should be fd_parent + 1 */
+	fd = open("open_plusplus_fd", O_CREAT|O_RDWR, 0660);
+	if (fd != fd_parent + 1) {
+		return 2;
+	}
+
+	/* Also, writing to fd_parent should succeed */
+	if (write(fd_parent, buf, sizeof(buf)) <= 0) {
+		return 3;
+	}
+
+	return 0;
+}
+