Quick and dirty but it'll work for you:
Write to file:
<?php
$fn = "C:/text/FileTest2.txt";
$text = "Appended to file:\n";
$file = @fopen($fn, "w+"

or die("Unable to open file"

;
@fwrite($file, $text) or die("Write to file failed."

;
$msg = "Write to file succeeded";
fclose($file);
?>
<html>
<head>
<title>File Write</title>
</head>
<body>
<?php echo $msg; ?>
</body>
</html>
--------------------
Read from file
<?php
$file = "C:/text/FileTest2.txt";
$fp = fopen( $file, "r" );
$data = nl2br(fread( $fp, filesize( $file)));
$data = explode(":", $data );
$len = count( $data )-1;
fclose( $fp );
//echo $data[1];
echo 'Number of lines in file are: ' . $len. '<BR>';
for( $x = 0; $x < $len; $x++)
{
echo $data[$x];
}
?>
--------------------