Re: messages override minibuffer input

[Richard Stallman]

    When I have written timers that produced output, it has been
    "informational" output which is not critical to see; then I have merely
    skipped printing unless the echo area either is empty or contains my
    timer's previous output, and the minibuffer is not active.  Would this be
    a good general function to provide?

Can you look for places in the sources where it would be right to use
`optional-message'?  If you find many, then the function would be a good
feature.

    I suppose some provision could be made for putting the message into
    *Messages* even if it's not displayed, but I'm not sure what the best way
    to do that is.

You can write Lisp code to do the same things now done at C level.  We
could also turn that C code into a subr, if that is useful.