I know there is an HTTP error log in ~/logs//http/error, but it contains nothing about PHP errors for my sites. On other hosts I've used, there has been a separate PHP error log which shows error and/or debugging output from PHP itself. I don't get any of this in my error log, instead, errors, warnings, etc. are printed directly to the user. How can I get this output in the error log instead?
I'm running PHP as CGI, for what it's worth.