diff --git a/src/Symfony/Component/Console/Application.php b/src/Symfony/Component/Console/Application.php
index 9dcafb3d21..9010fcae86 100644
--- a/src/Symfony/Component/Console/Application.php
+++ b/src/Symfony/Component/Console/Application.php
@@ -864,14 +864,16 @@ class Application implements ResetInterface
 
         if (true === $input->hasParameterOption(['--no-interaction', '-n'], true)) {
             $input->setInteractive(false);
-        } elseif (\function_exists('posix_isatty')) {
+        } else {
             $inputStream = null;
 
             if ($input instanceof StreamableInputInterface) {
                 $inputStream = $input->getStream();
             }
 
-            if (!@posix_isatty($inputStream) && false === getenv('SHELL_INTERACTIVE')) {
+            $inputStream = !$inputStream && \defined('STDIN') ? STDIN : $inputStream;
+
+            if ((!$inputStream || !stream_isatty($inputStream)) && false === getenv('SHELL_INTERACTIVE')) {
                 $input->setInteractive(false);
             }
         }
diff --git a/src/Symfony/Component/Console/Output/StreamOutput.php b/src/Symfony/Component/Console/Output/StreamOutput.php
index b7caa91382..6ffd9d1279 100644
--- a/src/Symfony/Component/Console/Output/StreamOutput.php
+++ b/src/Symfony/Component/Console/Output/StreamOutput.php
@@ -109,16 +109,6 @@ class StreamOutput extends Output
                 || 'xterm' === getenv('TERM');
         }
 
-        if (\function_exists('stream_isatty')) {
-            return @stream_isatty($this->stream);
-        }
-
-        if (\function_exists('posix_isatty')) {
-            return @posix_isatty($this->stream);
-        }
-
-        $stat = @fstat($this->stream);
-        // Check if formatted mode is S_IFCHR
-        return $stat ? 0020000 === ($stat['mode'] & 0170000) : false;
+        return stream_isatty($this->stream);
     }
 }
diff --git a/src/Symfony/Component/VarDumper/Dumper/CliDumper.php b/src/Symfony/Component/VarDumper/Dumper/CliDumper.php
index 207b716ea5..78290cdcc0 100644
--- a/src/Symfony/Component/VarDumper/Dumper/CliDumper.php
+++ b/src/Symfony/Component/VarDumper/Dumper/CliDumper.php
@@ -587,17 +587,7 @@ class CliDumper extends AbstractDumper
                 || 'xterm' === getenv('TERM');
         }
 
-        if (\function_exists('stream_isatty')) {
-            return @stream_isatty($stream);
-        }
-
-        if (\function_exists('posix_isatty')) {
-            return @posix_isatty($stream);
-        }
-
-        $stat = @fstat($stream);
-        // Check if formatted mode is S_IFCHR
-        return $stat ? 0020000 === ($stat['mode'] & 0170000) : false;
+        return stream_isatty($stream);
     }
 
     /**