diff --git a/framework/caching/FileCache.php b/framework/caching/FileCache.php
index 919a05a5893..08f292084e9 100644
--- a/framework/caching/FileCache.php
+++ b/framework/caching/FileCache.php
@@ -144,7 +144,7 @@ protected function setValue($key, $value, $duration)
         // If ownership differs the touch call will fail, so we try to
         // rebuild the file from scratch by deleting it first
         // https://github.com/yiisoft/yii2/pull/16120
-        if (is_file($cacheFile) && fileowner($cacheFile) !== posix_geteuid()) {
+        if (is_file($cacheFile) && function_exists('posix_geteuid') && fileowner($cacheFile) !== posix_geteuid()) {
             @unlink($cacheFile);
         }
         if (@file_put_contents($cacheFile, $value, LOCK_EX) !== false) {