Navigating with uexplore

If you have used the explore application in Windows 95 then you should have a good general idea of how the uexplore program works. It's just that it works on files on a UNIX server accessed via the Web instead of files on your desktop or on a PC network drive.

Once you have initiated the uexplore program (see the previous chapter) it is quite simple to move among the files and directories presented to you. The first page you should see is a table-of-contents HTML page that lists the name and (in most cases) a brief description of each file and subdirectory within the current directory. Most of the filenames are hyperlinks. A few files (displayed normally in black instead of the blue noramlly used to indicate links) will not be links for various reasons as discussed in the Basics of the MCDC Data Space chapter. Entries that have a trailing "/" are themselves directories; clicking on one of these will bring up the corresponding table-of-contents page for that directory. Clicking on links to non-directory files will result either in the file being displayed in your browser, or it may trigger a special application if it is recognized as a SAS dataset. You can, of course, use your browser's back key at any time to reverse the path you have traveled. So if you open a directory and decide there is nothing there for you simply go back to the previous menu page.

Select a SAS application with sasapps.pl

Any file that has an extension of ssd01 or ssv01 is a SAS dataset that contains actual data (not just text, but binary format data comprised of observations and variables.) When you select one of these files the hyperlink invokes a special intermediate cgi-bin application (wirtten in the Perl language, as is the uexplore module) called sasapps.pl . A special intermediate menu page will be generated which will contain a drop-down menu with a list of SAS applications (i.e. programs written in SAS that know about the information contained in this dataset) that can be run against the selected dataset. At this time (9/97) there are only three such applications. Two of these, hypercon and xtract, are universal -- meaning they can be run against any SAS dataset. The third, called tabrgen (Table Report Generator) is only available for a select group of 1980 and 1990 STF filetypes. The default application is xtract; if you simply click on the Run Request button, that application's main menu will be presented next. If you click on the drop-down menu you can select one of the other applications. The hypercon application has two options, depending on whether you want to see hypercon's metadata summary report for each of the SAS files in the directory, or whether you only want to see information about the current file. You can always use the back button if you decide none of the options is what you want. Each of these three SAS applications is discussed in depth in its own chapter of this tutorial.

Note: if your intention is to use xtract to pull data from a specific dataset, but you want to use hypercon to review the variables in the dataset first, you can still go ahead and select xtract as your application. You'll find an easy link to hypercon from the second and third pages of the xtract application.