gmail automatic labels/filters...

hi, i need some help. i manage my business email using a gmail account. my aim is to automatically label the email i receive (thousands every month) letting a script choose the right label by reading the email content. i can do the (bash) script to determine the right label, but i don't know how to tell gmail to apply (and create, if needed) the label. idea: 1) check for new emails 2) analyze the content of the new emails and determine the label to apply (i can do this) 3) apply the label to the current email, leaving it "unread" the most interesting information i found on internet is this: [login to view URL] no idea on how to use it... :o( matteo