Snort and alert file

["Justin Tabish" <admin () illusivedream com>]

Been running snort for 3 days and I've been getting portscans and unprivliaged accesses to my system yet my alert file 
is 0bytes ... How can I fix this cause I would like to have this thing work. I do not use -A Full and I'm using the 
most current rulesets from snort.org