diff --git a/func/string.php b/func/string.php
new file mode 100644
index 00000000..986e9541
--- /dev/null
+++ b/func/string.php
@@ -0,0 +1,13 @@
+<?php
+
+function myvesta_replace_in_file($file, $find, $replace) {
+    if (!file_exists($file)) return myvesta_throw_error (3, "File '$file' not found");
+
+    $buf=file_get_contents($file);
+
+    if (strpos($buf, $find)===false) return myvesta_throw_error (4, "String '$find' not found");
+
+    $buf=str_replace($find, $replace, $buf);
+    $r=file_put_contents($file, $buf);
+    return $r;
+}