[PHP] Open read & write access to process

Hi all, I read from the php document that I can use the popen function to open either read or write access to a system process, is it possible to open read and write access at the same time? I tried popen with "w+" but it doesn't work. Anyone have solution to this? FYI, I am using php 4.0

[PHP] popen

Hi, is anyone know how to make popen command to read and write to a process at the same time? My php script need to call linux command which requires interactive action, or anyone know other possible way of doing it? Regards, Lau NH