Passing variable from parent to child window???

Not sure if this is possible, but I am trying to set up a system where, upon clicking a link on a page, a child window opens and when an option on the child window is selected it updates the parent. This much of the process I have completed. The only problem is that I can onl update the parent if I know the name of the element to update. Is there anyway to pass a variable to a child window using the open function? I was thinking of using the 'name' parameter of the open function, but do not know if it is possible to retrieve that information from the child window.

Anyone have any suggestions?

UPDATE:
Ok I've managed to solve the problem! I kind of cheated because I don't really pass a variable to the cihld, instead I created a hidden input field on the parent window. When the child is opened, the variable I wished to pass is inserted into the hidden field and the child reaches back to the parent and references that hidden field to obtain the variable! Not sure is there is a beter way or not, but this worked fine for me!

flashbck,

Your question has been answered about 5 times in this forum already, please use search and you'll find the proper way to pass variables around, between parents & children.