diff --git a/src/Symfony/Component/Process/Process.php b/src/Symfony/Component/Process/Process.php
index 0c6f40c707..27df1361e9 100644
--- a/src/Symfony/Component/Process/Process.php
+++ b/src/Symfony/Component/Process/Process.php
@@ -976,16 +976,9 @@ class Process implements \IteratorAggregate
         if ('\\' === DIRECTORY_SEPARATOR && $tty) {
             throw new RuntimeException('TTY mode is not supported on Windows platform.');
         }
-        if ($tty) {
-            static $isTtySupported;
 
-            if (null === $isTtySupported) {
-                $isTtySupported = (bool) @proc_open('echo 1 >/dev/null', array(array('file', '/dev/tty', 'r'), array('file', '/dev/tty', 'w'), array('file', '/dev/tty', 'w')), $pipes);
-            }
-
-            if (!$isTtySupported) {
-                throw new RuntimeException('TTY mode requires /dev/tty to be read/writable.');
-            }
+        if ($tty && !self::isTtySupported()) {
+            throw new RuntimeException('TTY mode requires /dev/tty to be read/writable.');
         }
 
         $this->tty = (bool) $tty;
@@ -1169,6 +1162,22 @@ class Process implements \IteratorAggregate
         }
     }
 
+    /**
+     * Returns whether TTY is supported on the current operating system.
+     *
+     * @return bool
+     */
+    public static function isTtySupported()
+    {
+        static $isTtySupported;
+
+        if (null === $isTtySupported) {
+            $isTtySupported = (bool) @proc_open('echo 1 >/dev/null', array(array('file', '/dev/tty', 'r'), array('file', '/dev/tty', 'w'), array('file', '/dev/tty', 'w')), $pipes);
+        }
+
+        return $isTtySupported;
+    }
+
     /**
      * Returns whether PTY is supported on the current operating system.
      *