文件存在，但我无法使用PHP打开它

I can open and write in file using vim command but i cant open it using PHP

$myFile = "v.txt"; 
if(!file_exists($myFile)){
    print 'File not found';
}else if(!$fh = fopen($myFile, 'w+')){
    print 'Can\'t open file 
';}.
else{  
    print 'Success open file';
}

Do a

ls -l

on the directory that contains the file. Make sure the user that's running your web server has access read rights to the file