In order to exit from Poplog or its editor there are various different commands, performing slightly different functions. Which command you should use can also depend on which context you are in.
Further information follows.
If there are any such files, then they will automatically be saved. If you are not using Pop-11 but one of the other Poplog languages, and are typing to its prompt, outside the editor, you can also quit in that way. All it does in that context is terminate immediate mode. That should cause Poplog to abort and take you back to the Unix or VMS command line. The terminal handling software may then not be set right.