diff --git a/libbuild2-autoconf/libbuild2/autoconf/checks/HAVE_PIPE.h b/libbuild2-autoconf/libbuild2/autoconf/checks/HAVE_PIPE.h
new file mode 100644
index 0000000..e990465
--- /dev/null
+++ b/libbuild2-autoconf/libbuild2/autoconf/checks/HAVE_PIPE.h
@@ -0,0 +1,19 @@
+// HAVE_PIPE : BUILD2_AUTOCONF_LIBC_VERSION
+
+#ifndef BUILD2_AUTOCONF_LIBC_VERSION
+#  error BUILD2_AUTOCONF_LIBC_VERSION appears to be conditionally included
+#endif
+
+#undef HAVE_PIPE
+
+/* Since Version 3 AT&T UNIX (older than 1979).
+ * Linux, FreeBSD, OpenBSD, NetBSD, Mac OS X, Solaris
+ */
+#if defined(__linux__)                    || \
+    defined(__FreeBSD__)                  || \
+    defined(__OpenBSD__)                  || \
+    defined(__NetBSD__)                   || \
+    defined(BUILD2_AUTOCONF_MACOS)        || \
+    ((defined(__sun) && defined(__SVR4)) || defined(__sun__))
+#  define HAVE_PIPE 1
+#endif
diff --git a/libbuild2-autoconf/libbuild2/autoconf/checks/HAVE_PIPE2.h b/libbuild2-autoconf/libbuild2/autoconf/checks/HAVE_PIPE2.h
new file mode 100644
index 0000000..da944c8
--- /dev/null
+++ b/libbuild2-autoconf/libbuild2/autoconf/checks/HAVE_PIPE2.h
@@ -0,0 +1,17 @@
+// HAVE_PIPE2 : BUILD2_AUTOCONF_LIBC_VERSION
+
+#ifndef BUILD2_AUTOCONF_LIBC_VERSION
+#  error BUILD2_AUTOCONF_LIBC_VERSION appears to be conditionally included
+#endif
+
+#undef HAVE_PIPE2
+
+/* Since OpenBSD 5.7, FreeBSD 10.0, NetBSD 6.0,
+ * glibc 2.9.
+ */
+#if BUILD2_AUTOCONF_OPENBSD_PREREQ(201505) || \
+    BUILD2_AUTOCONF_FREEBSD_PREREQ(10, 0)   || \
+    BUILD2_AUTOCONF_NETBSD_PREREQ(6, 0)    || \
+    BUILD2_AUTOCONF_GLIBC_PREREQ(2, 9)
+#  define HAVE_PIPE2 1
+#endif