What potential issues can arise when dynamically updating a log file in PHP?

Potential issues that can arise when dynamically updating a log file in PHP include file locking problems, concurrent access issues, and potential data corruption if multiple processes try to write to the log file simultaneously. To solve these issues, you can use file locking mechanisms to ensure that only one process can write to the log file at a time.

$logfile = 'logfile.txt';

$fp = fopen($logfile, 'a');
if (flock($fp, LOCK_EX)) {
    fwrite($fp, "Log message\n");
    flock($fp, LOCK_UN);
} else {
    echo "Could not lock file!";
}
fclose($fp);