@gits
thanks for that suggestion!
i have realized though that my initial goal won't work. yes, i do want the browser to reload a text file after the user modifies it. but the sequence of events in the scripts requires something, too.
let me explain:
1) page loads, and page calls up the text-file-database.
2) that file is parsed...
3) ...into an array of data points.
so it would not be enough to reload the text file.
i realize my goal really is to make the new datapoint accessible to the user who just inputted it.
one way to do that -- have the user reload the whole page after he adds a datapoint.
the problem i have encountered is that browsers cache that old text-file-database. so even reloading the page will not force a download of the updated text file.
so new questions: is there a way to make the page download the text file each time the page loads, regardless of the browser's cache settings? or a way to stop the text file from ever being saved in the cache? -- though i need it to be in memory long enough to be parsed?
the alternative to the above -- and the above seems much easier to me intuitively -- is to have the data point added to the array. the problem is that the main page runs the map. and the script that adds data points runs in an "infowindow" -- those little popup windows you see in Google Maps and mashups. so i am not sure whether the script can add to the array in the main page.
any ideas here?