From 7660d59bfab2ae2002fb7b594f89932ccea626ee Mon Sep 17 00:00:00 2001
From: Martin Oberhuber <martin.oberhuber@windriver.com>
Date: Fri, 28 Oct 2016 23:15:23 +0200
Subject: [PATCH 1/2] ConfigureChecks: libutil is now optional. See #163

---
 cmake/ConfigureChecks.cmake | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/cmake/ConfigureChecks.cmake b/cmake/ConfigureChecks.cmake
index 863213f81..874224f9e 100644
--- a/cmake/ConfigureChecks.cmake
+++ b/cmake/ConfigureChecks.cmake
@@ -358,7 +358,9 @@ if(HAVE_BUILTIN_OPENPTY)
   set(HAVE_LIBUTIL 1)
 else()
   find_library(HAVE_LIBUTIL util)
-  set(LIBUTIL_LIBRARIES ${HAVE_LIBUTIL})
+  if(HAVE_LIBUTIL)
+    set(LIBUTIL_LIBRARIES ${HAVE_LIBUTIL})
+  endif()
 endif()
 
 if(APPLE)

From 046ad41ad1986ec31743d6358b67364448d8d9eb Mon Sep 17 00:00:00 2001
From: Jean-Christophe Fillion-Robin <jchris.fillionr@kitware.com>
Date: Thu, 3 Nov 2016 16:44:27 -0400
Subject: [PATCH 2/2] ConfigureChecks: Add support for system not expecting
 "libutil" (e.g VxWorks)

See #163
---
 cmake/ConfigureChecks.cmake | 33 ++++++++++++++++++++++++---------
 1 file changed, 24 insertions(+), 9 deletions(-)

diff --git a/cmake/ConfigureChecks.cmake b/cmake/ConfigureChecks.cmake
index 874224f9e..ae30ba31c 100644
--- a/cmake/ConfigureChecks.cmake
+++ b/cmake/ConfigureChecks.cmake
@@ -351,15 +351,30 @@ endif()
 find_library(HAVE_LIBTERMCAP termcap)
 
 set(LIBUTIL_LIBRARIES )
-check_function_exists("openpty" HAVE_BUILTIN_OPENPTY)
-if(HAVE_BUILTIN_OPENPTY)
-  # Libutil functions are builtin the environment (e.g emscripten)
-  set(LIBUTIL_LIBRARIES )
-  set(HAVE_LIBUTIL 1)
-else()
-  find_library(HAVE_LIBUTIL util)
-  if(HAVE_LIBUTIL)
-    set(LIBUTIL_LIBRARIES ${HAVE_LIBUTIL})
+set(LIBUTIL_EXPECTED 1)
+
+if(CMAKE_SYSTEM MATCHES "VxWorks\\-7$")
+  set(LIBUTIL_EXPECTED 0)
+  set(HAVE_LIBUTIL 0)
+endif()
+
+if(LIBUTIL_EXPECTED)
+  check_function_exists("openpty" HAVE_BUILTIN_OPENPTY)
+  if(HAVE_BUILTIN_OPENPTY)
+    # Libutil functions are builtin the environment (e.g emscripten)
+    set(LIBUTIL_LIBRARIES )
+    set(HAVE_LIBUTIL 1)
+  else()
+    if(NOT DEFINED HAVE_LIBUTIL OR "${HAVE_LIBUTIL}" STREQUAL "")
+      find_library(HAVE_LIBUTIL util)
+      if(HAVE_LIBUTIL)
+        set(LIBUTIL_LIBRARIES ${HAVE_LIBUTIL})
+      endif()
+      message(STATUS "Found libutil: ${HAVE_LIBUTIL}")
+    endif()
+  endif()
+  if(NOT HAVE_LIBUTIL)
+    message(FATAL_ERROR "Could NOT find libutil (missing: HAVE_LIBUTIL)")
   endif()
 endif()