the api to the system component that is it contains all of the entry points to the system component api with some additional entry points the patch shell 11 communicates with a database of syndromes 12 the features associated with patch shell depicted in fig2 b are a particular advantage of the present invention and will be described in greater detail it can be seen from the figure and the description above that any use of system component 10 can be accomplished with equivalent use of patch shell 11 in fact some of the entry points to the api of the patch shell may be identical to the entry points to the api of the system component those that are not are said to be u201c monitored u201d monitored api calls are first checked by the patch shell to see if they match any invocation syndromes if they do it may be the case that this call invokes behavior for which a patch exists but where the patch has not yet been applied not shown in fig2 is reference by the patch shell to a policy database which controls what to do in this situation fig3 is a flow diagram that illustrates the processing performed by the patch shell the patch shell is a monitor that is invoked when a call is made to its api thus it is shown in the figure as executing continuously in block 20 the patch shell waits for the next invocation of a monitored entry point of the system component 39 s api in block 21 the arguments and identity of the entry point are captured and in the decision block.