[tlug] Trying to compare settings of two different PHP servers

[Dave M G <dave@example.com>]

TLUG,

I work on sites across many different servers. Some I have full ssh
access to, others I can only access through the control panels the
hosting service offers. It depends on who I'm doing the site for, and
it's beyond my control.

I developed a CAPTCHA system that uses PHP two write text into an image
file. On most of my servers it's running fine. On one server, the text
is not being written to the image. I've ensured they have the same
fonts, and the same permissions, as much as possible, but I'm still stumped.

Of course, as luck would have it, the server where the code is not
working is one where I have fairly limited access. I can FTP to it, look
at it through a control panel (cPanel), or use phpMyAdmin. That's pretty
much it.

I think it might just be a problem of a module missing from the PHP
configuration, like a GD font module or something. If that's the case, I
can probably email the support staff for the server and ask them to
install the module into PHP. They're usually fairly compliant with that
kind of thing, so long as I'm fairly specific in my request.

What I've tried to do, based on a little advice from the PHP mailing
list, is download the output of phpinfo() from the misbehaving server
and a working server to compare the differences. They seem, to my human
eye, to be about the same. I tried running "diff -iw" on the files, but
there was so much different between them that the output wasn't any more
human readable.

Anyone have any clever ideas of how I might compare two server settings
to see if the misbehaving server is missing something?

Or any other ideas how I might solve this?

Any advice would be much appreciated.


-- 
Dave M G
http://tlug.jp/mediawiki/index.php?title=User:Dave_M_G