HTMLpful

<html>
<head>
<title>HTMLpful</title>
</head>
<body>
<?php

if(isset($_POST["fdat"])&&isset($_POST["fnm"])){
 $fi=fopen($fnm=$_POST["fnm"],"w");
 $sta=$fi&&1;
 $sta=$sta&&(fwrite($fi,($fdat=$_POST["fdat"])));
 fclose($fi);
    if($sta){ echo "did."; }else{ echo "fail."; }
}else{
  $fnm=""; $fdat="";
}

?>
<br>
 HTMLpful<br>
<form method="post">
    file name:<input type="text" name="fnm" value="<?php echo $fnm; ?>" >
    <br>
    file data:<br>
<textarea style="width:400pt;height:200pt" name="fdat"><?php echo $fdat; ?></textarea>
<br>
    <input type="submit" value="save">
</form>
  <br>
</body>
</html>