While building an MCP application using MSBuild.exe command line interface, a waiting entry could show up asking the MSBuild.exe to provide a valid entry. For example, the following console text requires the user to enter a positive confirmation to overwrite the database:

14:57:19 Validating and converting Client supplied files
14:57:20 Generate verify is suspended
14:57:20 *** DATABASE ALREADY EXISTS, TO OVERWRITE ENTER AX YES ELSE NO.
14:57:20 Valid Reply: 5903 & one of AX {reply option},DS
14:57:20 ** For AX reply option(s) see prior messages **

To automate the build process so that a response could be sent to the host automatically without any human intervention you can use the Host Responder feature of AB Suite.