Writes a file without the worry on simultaneous file writings.

writeDataToFileSafely.php

/**
 * Writes a file without the worry on simultaneous file writings.
 *
 * @param mixed $data - Data to put into the file.
 * @param string $filePath - Path to the file to put data into.
 * @param number $timeOut - The maximum time (milliseconds) until method attempts to write file (defaults to 1000).
 * @return bool - Returns true if data has been written.
 */
function writeDataToFileSafely($data, $filePath, $timeOut = 1000)
{
    $interval = 10; // milliseconds
    $elapsed = 0;
    $success = false;

    while($success === false && $elapsed < $timeout)
    {
        $success = file_put_contents($filePath, $data, LOCK_EX);
        usleep(interval * 1000); // to microseconds
        $elapsed += $interval;
    }

    return $success;
}