The loadobject -unload command unloads specified load objects. It is valid only in native mode.
loadobject -unload [regexp]
regexp is a regular expression. If it is not specified the command applies to all load objects.
This command unloads the symbols for any load objects matching the regexp supplied on the command line. The main program loaded with the debug command cannot be unloaded. dbx may also refuse to unload other load objects that might be currently in use, or critical to the proper functioning of dbx.