xml saving to a file?

hi, i'm doing this scripting where by i need to add additional xml tags through the web into the xml file. Whenever a user enter a tag or some text, and click update, I need to update the xml file directly. My teacher say to use Javascript DOM and XPath will help. But i notice there's no saving to a file function.? Must i use ASP to achieve what i want? Is there any way using javascipt DOM and Xpath so that i no need to use ASP?

Thank you!!!!!!!!

You can amend an xml file with javascript but you cannot save it directly without using server-side functionality (or VBscript). The best you can do with javascript is to write the amended file to a new window, and then cut and paste the contents into a text editor and save it from that.

patrick