I have found that ftp_size isn't supported on all servers. What is the determination if it is supported or not? Does it depend on the Operating System, or is it a php setting that just needs to be enabled?
I'm trying to use it to determine what is a directory and what is a file. I have also attempted to use ftp_rawlist but ran into a road block, as well as ftp_chdir but there is slowness issues when you have to change directories as you are looping through.