Use DIRECTORY_SEPARATOR in powerfs plugin for operation_id file.

Author: cdujeu

core/src/plugins/action.powerfs/class.PowerFSController.php

@@ -99,7 +99,7 @@ public function switchAction($action, $httpVars, $fileVars)
 
             case "postcompress_download":
 
-                $archive = AJXP_Utils::getAjxpTmpDir()."/".$httpVars["ope_id"]."_".$httpVars["archive_name"];
+                $archive = AJXP_Utils::getAjxpTmpDir().DIRECTORY_SEPARATOR.$httpVars["ope_id"]."_".$httpVars["archive_name"];
                 $fsDriver = AJXP_PluginsService::getInstance()->getUniqueActivePluginForType("access");
                 if (is_file($archive)) {
                     register_shutdown_function("unlink", $archive);
@@ -163,7 +163,7 @@ public function switchAction($action, $httpVars, $fileVars)
                 $cmdSeparator = ((PHP_OS == "WIN32" || PHP_OS == "WINNT" || PHP_OS == "Windows")? "&" : ";");
                 //$archiveName = SystemTextEncoding::fromUTF8($httpVars["archive_name"]);
                 if (!$compressLocally) {
-                    $archiveName = AJXP_Utils::getAjxpTmpDir()."/".$httpVars["ope_id"]."_".$archiveName;
+                    $archiveName = AJXP_Utils::getAjxpTmpDir().DIRECTORY_SEPARATOR.$httpVars["ope_id"]."_".$archiveName;
                 }
                 chdir($rootDir);
                 $cmd = $this->getFilteredOption("ZIP_PATH")." -r ".escapeshellarg($archiveName)." ".implode(" ", $args);