wscript.shell使用php运行路径中有空格的文件

我试图使用wscript.shell通过带有php的com对象将一些命令传递给curl库(dos版本)。以下是我用来执行此任务的内容:

function windExec($cmd,$mode=''){
    // Setup the command to run from "run"
    $cmdline = "cmd /C $cmd";

    // set-up the output and mode
    if ($mode=='FG'){
        $outputfile =  uniqid(time()) . ".txt";
        $cmdline .= " > $outputfile";
        $m = true;
    }
    else $m = false;

    // Make a new instance of the COM object
    $WshShell = new COM("WScript.Shell");

    // Make the command window but dont show it.
    $oExec = $WshShell->Run($cmdline, 0, $m);

    if ($outputfile){
        // Read the tmp file.
        $retStr = file_get_contents($outputfile);
        // Delete the temp_file.
         unlink($outputfile);
    }
    else $retStr = "";

    return $retStr;
}

现在,当我运行这个函数时:

windExec("\"C:/Documents and Settings/ermac/Desktop/my project/curl\" http://www.google.com/", 'FG');

curl不运行,因为路径有问题。但是当我把这些空间从小路上移开的时候,效果很好。

windExec("\"C:/curl\" http://www.google.com/", 'FG');

所以我的问题是如何在wscript.shell命令中转义这些空格? 我能解决这个问题吗?

提前谢谢:)