PHP Read and write file operation

function Read ($filename, $filesze)
{
$FP =fopen ($filename, "RB");//Fopen RB property read file and unlock with flock Lock_sh,lock_un
if ($FP)
{
Flock ($FP, lock_sh);
Clearstatcache ();
$filesize =filesize ($filename);
if ($filesize >0)
{
$data =fread ($fp, $filesize);
}else
{
$data =false;
}
Flock ($FP, lock_un);
Fclose ($FP);
return $data;
}else
{
return false;
}
}

/**
* Write files with fopen
* @param string $filename
* @param string $contents
* @return Boolean
*/

function Wirte ($filename,& $contents)
{
$FP =fopen ($filename, "WB");
if ($FP)
{
Flock ($FP, LOCK_EX);//Lock file at the same time, only one person can operate
Fwrite ($fp, $contents);
Flock ($FP, lock_un);//save data grip for unlock file and save
Fclose ($FP);
return true;
}else
{
return false;
}
}

Apply 1 read files, 2 write files
$body = ';
if ($a = 1)
{
Read (' A.txt ', 1024);
}
Else
{
Wirte (' A.txt ', $body);
}
Output file
Echo $body;
?>