catgets catHandle setnum msgnum defaultstr
          Retrieve a message form a  message  catalog.  CatHandle
          should  be  a  Tcl  message  catalog  handle  that  was
          returned by catopen.  Setnum is the message set number,
          and  msgnum is the message number. If the message cata-
          log was not opened,  or  the  message  set  or  message
          number  cannot  be  found,  then  the  default  string,
          defaultstr, is returned.

          This command is provided by Extended Tcl.