deletelf - remove an existing RMSfile
Deletelf removes the contents, data dictionary, and the database catalog
entry for an RMSfile that is no longer needed. Once an RMSfile has been
removed with deletelf it is no longer accessible to any program.
If the datafile argument has the form dbname~lfile or ~lfile, then
deletelf deletes the RMSfile named by using the database dbname and
logical file name lfile. If the datafile argument has the form filename
(i.e. it has neither a ~ nor / in the name), then it is taken as a
logical file name, filename, using the default database name.