What techniques can be used to control positions in a Streamreader based on conditions in PHP?

When using a Streamreader in PHP, you can control positions based on conditions by using the `fseek` function to move the pointer to a specific position in the stream. You can use conditional statements to determine when to seek to a new position based on certain conditions in the data being read.

$filename = "example.txt";
$stream = fopen($filename, "r");

// Read the first line
$line = fgets($stream);

// Check if the line meets a certain condition
if (strpos($line, "keyword") !== false) {
    // Move the pointer to a specific position in the stream
    fseek($stream, 0);
}

fclose($stream);