OK, with the data retrieval methods indicated earlier, we've got her licked. Part of my remaining problem was that I was calling the connection by a name other than the alias I'd assigned it. The following works:

\r\n\r\n
\r\n
\r\n484  /* Get OLEDB connection info */\r\n485  proc sql;\r\n486      connect to oledb as bar (\r\n487          Provider=MSDASQL.1\r\n488          properties=("Data Source"="SQLDAT")\r\n489          );\r\n490      select * from connection to bar (select * from sysfiles);\r\n491  quit;\r\nNOTE: PROCEDURE SQL used:\r\n      real time           0:00:00.03\r\n      cpu time            0:00:00.01\r\n
\r\n
\r\n\r\n

Note that the name of the connection in the second statement matches the alias above. I was stumbling on that minor detail....

\r\n\r\n

Connection settings were uncovered using the dd trick above, and with the &SYSDBMSG SAS automatic macrovariable (%PUT &SYSDBMSG; immediately following an interactive connection).