From 42a76e3da675f34415a6286af4e7eac66516a54f Mon Sep 17 00:00:00 2001
From: Robert Kloefkorn <robert.kloefkorn@iris.no>
Date: Mon, 9 May 2016 16:58:07 +0200
Subject: [PATCH] SimulatorFullyImplicitBlackoilOutput: use HAVE_PTHREAD to
 enable async_output by default.

---
 .../SimulatorFullyImplicitBlackoilOutput.hpp  | 22 ++++++++++++++-----
 1 file changed, 16 insertions(+), 6 deletions(-)

diff --git a/opm/autodiff/SimulatorFullyImplicitBlackoilOutput.hpp b/opm/autodiff/SimulatorFullyImplicitBlackoilOutput.hpp
index 5ad844bb4..529317109 100644
--- a/opm/autodiff/SimulatorFullyImplicitBlackoilOutput.hpp
+++ b/opm/autodiff/SimulatorFullyImplicitBlackoilOutput.hpp
@@ -302,12 +302,6 @@ namespace Opm
         eclipseState_(eclipseState),
         asyncOutput_()
     {
-        // create output thread if needed
-        if( output_ && param.getDefault("async_output", bool( false ) ) )
-        {
-            asyncOutput_.reset( new ThreadHandle() );
-        }
-
         // For output.
         if (output_ && parallelOutput_->isIORank() ) {
             // Ensure that output dir exists
@@ -319,6 +313,22 @@ namespace Opm
                 OPM_THROW(std::runtime_error, "Creating directories failed: " << fpath);
             }
 
+            // create output thread if enabled and rank is I/O rank
+            // async output is enabled by default if pthread are enabled
+#if HAVE_PTHREAD
+            const bool asyncOutputDefault = true;
+#else
+            const bool asyncOutputDefault = false;
+#endif
+            if( param.getDefault("async_output", asyncOutputDefault ) )
+            {
+#if HAVE_PTHREAD
+                asyncOutput_.reset( new ThreadHandle() );
+#else
+                OPM_THROW(std::runtime_error,"Pthreads were not found, cannot enable async_output");
+#endif
+            }
+
             std::string backupfilename = param.getDefault("backupfile", std::string("") );
             if( ! backupfilename.empty() )
             {