Now the question is, what is a filetype? This is the tricky part. The details of the archive's directory space are discussed in more detail in the Basics of the /mscdc/data space chapter. Most of the data you'll want to explore is stored in some subdirectory of the /mscdc/data or /pub/data. The word "<filetype>" here stands for that "a particular subdirectory". The term filetype is used to refer to the basic categories to which have been assigned to each of our data files. Each filetype corresponds to a subdirectory of a particular directory. So, for example, if I type in the URL:

  http://www.oseda.missouri.edu/cgi-bin/uexplore?/mscdc/data/popests@secure

I would be indicating that "I want to run the uexplore program to look at all the files you've got classified as type popests". These are, as you might expect, various files having information pertaining to population estimates. If this works, the result of entering the above URL should be a page showing the "Contents" of this directory. What happens next is covered later.

If it does not work, it usually indicates that typo has been made. If the typo occurred before the parameter value (i.e. to the left of the "?") you'll usually get a "404 Not Found" message returned to your browser. If the error occurs in the entering of the path value, then you'll get a message saying "There is no Contents file in this directory." This is actually a misleading message, because it sort of implies that the directory exists, but just does not contain a "Contents file" (whatever that is.) As it turns out, you also get this message when the directory does not exist at all. Some day we'll fix this. It is actually very rare -- at least with directories under the /mscdc/data path -- for a subdirectory to really not have a Contents file.

Too complicated for you?

There may be an easier way, if you want to take the guided tour instead of driving yourself around the directory. There are a number of web pages you can invoke that will assist you in starting your explorations of the MCDC data archive. Many of the subdirectories contain Readme or Techdocs which generally contains information on the file and other definitions.

If you feel that having to type in your own <filetype> value is too difficult (at least until you get to know your way around the place) and that the "guided tour" is more structure than you want or need, there is another way to go. Simply omit the <filetype> portion from the URL altogether, which will then present you with the Contents page for the entire archive (i.e. for the /mscdc/data directory.) This means you would enter the URL:

  http://www.oseda.missouri.edu/cgi-bin/uexplore?/mscdc/data@secure

If you are digitally challenged like me and have trouble typing such URLs without misshap, you can copy and paste the URL from this document or you can simply go ahead and go to any of the filetype directories using the http://mcdc.missouri.edu/applications/uexplore.html page. Then you can edit the URL as it appears in the Location window of your browser, truncating the "/popests" or whatever filetype is entered just to the left of the "@secure".

The Contents page for any subdirectory is not your normal cyberspace page. If you do not enter by way of "uexplore.html" the filetypes are arranged alphabetically, not logically. This entryway should be used by those who already know what filetype they are going to want and can quickly find it on this page, or for those adventurous souls who just want to see everything we've got (Programmer types, mostly). Be warned that there are some filetypes that we have spent many man-months on, getting ready for public access, and others on which we have spent almost no time. A few of the filetypes are really just placeholders for types of data that we do not yet have, or that we have not yet brought over from the old MVS mainframe system. So exploring here without a map (i.e. without specific instructions or annotated hyperlink pages) brings with it the risk of wasting some of your time. But then again, there are significant data treasures to be discovered.