I don't know if there's any? but is php built in web server also save its error logs in a file? for tailing purposes, like when creating virtual host in apache.
UPDATE: i'm using mac osx
The built-in webserver doesn't log anywhere by default, so you need to provide a php.ini for it to customise this. For example, if you created a file called php.ini with this content:
error_log = /Users/me/test.log
log_errors = on
date.timezone = UTC
Then you can start PHP's built-in webserver like this:
php -S 127.0.0.1:8080 -c php.ini
And error_log() calls will be logged to the file you've specified.