diff --git a/convert.php b/convert.php
index 2255c11..ede778c 100755
--- a/convert.php
+++ b/convert.php
@@ -50,7 +50,7 @@
 if (!$filePath) {
     file_put_contents('php://stderr', 'Usage: php convert.php [-w] <file>' . "\n");
     exit(1);
-} elseif (!file_exists($filePath)) {
+} elseif (!file_exists($filePath) && $filePath != 'php://stdin') {
     file_put_contents('php://stderr', 'File "' . $filePath . '" not found.' . "\n");
     exit(1);
 }
diff --git a/revert.php b/revert.php
index 087e79d..1b70fc5 100755
--- a/revert.php
+++ b/revert.php
@@ -50,7 +50,7 @@
 if (!$filePath) {
     file_put_contents('php://stderr', 'Usage: php revert.php [-w] <file>' . "\n");
     exit(1);
-} elseif (!file_exists($filePath)) {
+} elseif (!file_exists($filePath) && $filePath != 'php://stdin') {
     file_put_contents('php://stderr', 'File "' . $filePath . '" not found.' . "\n");
     exit(1);
 }