Merge pull request #153 from phaseinducer/patch-1

Add an exception in case of �proc_open() failure

src/Knp/Snappy/Process.php

@@ -58,22 +58,24 @@ public function run()
 
         $process = proc_open($this->command, $descriptorspec, $pipes, null, $this->env);
 
-        if (is_resource($process)) {
-            // $pipes now looks like this:
-            // 0 => writeable handle connected to child stdin
-            // 1 => readable handle connected to child stdout
-            // 2 => readable handle connected to child stderr
+        if (!is_resource($process)) {
+            throw new \RuntimeException('Unable to launch a new process.');
+        }
 
-            $this->output = stream_get_contents($pipes[1]);
-            fclose($pipes[1]);
+        // $pipes now looks like this:
+        // 0 => writeable handle connected to child stdin
+        // 1 => readable handle connected to child stdout
+        // 2 => readable handle connected to child stderr
 
-            $this->errorOutput = stream_get_contents($pipes[2]);
-            fclose($pipes[2]);
+        $this->output = stream_get_contents($pipes[1]);
+        fclose($pipes[1]);
 
-            // It is important that you close any pipes before calling
-            // proc_close in order to avoid a deadlock
-            $this->exitCode = proc_close($process);
-        }
+        $this->errorOutput = stream_get_contents($pipes[2]);
+        fclose($pipes[2]);
+
+        // It is important that you close any pipes before calling
+        // proc_close in order to avoid a deadlock
+        $this->exitCode = proc_close($process);
     }
 
     /**