Handling Macintosh filenames in PHP

Greetings all, I'm currently in the middle of developing a rather large piece of software written in PHP. I'll spare you the details, but essentially it is a glorified FTP client. The goal here, of course, is to develop a client that will work on any platform. In theory, this SHOULD work, because PHP runs server-side, therefore eliminating any problems that would normally arise from differences between the various platforms. However, it occurred to me that there isn't really a way (that I know of) to directly address a specific filename on a Macintosh as there is in other operating systems. For example, in Windows I could type C:\WINDOWS\SYSTEM\BLAH.EXE or in Unix I could type /var/spool/mail/whatever ... but is there a way to do such a thing on a Mac? Can you directly address a file several levels deep in the filesystem without using the MacOS interface itself to do so? The project I'm doing relies on the ability to do just that, and it would appear that I've hit a bit of a snag. If anyone can offer any suggestions or advice, I'd really appreciate it. Thanks in advance. Sincerely, Shawn Reed Chief Technology Officer RBC Incorporated - home of "Remote Backup Center" [ shawn@remotebackupcenter.com / www.remotebackupcenter.com ]