This module is well suited for certain kind of logging actions or giving feedback.

If independent applications feedback always as immediate answer to an interactive action, it is very reasonable to share a viewer for this feedback. That is where this module should be used most.

On the other side this package probably should not be used when independent processes or applications make output at random times; in this case, these applications should better have a feedback area of their own.

This module takes care of the existence, creation and interactive deletion of its viewers; clients will not get any errors or signals on outputs. Inputs may raise UserAbort or TimeOut, but only where mentioned in the definitions module.

The input routines are a poor man's routines; they require the user to really make the input (or abort) because the package will not do any other operations until the input is finished. For simple applications this might even be what is wanted. It is specially conveniant for applications which are extended on the fly to have an easy IO handling module; Extensions are eased if they need not deal with viewer creation of the main application.

The strict following of the input convention guarantees that the user is not forced to switch his awarness to a different application at random times.

The fact that users can always abort input guarantees that client programs can not lock other clients out of doing feedback. (The private procedure AddLock is the exception; thats why this procedure is private.)