this must be a common problem, but repeated searching is not finding an answer

[Brian Inglis]

On Sat, 19 Mar 2022 08:12:15 -0700, Achim Gratz wrote:
> Clayton Cramer writes:
>> I installed everything from the setup program, but executing bc gives
>> "The code execution cannot proceed because readline4.dll was not
>> found.  Reinstalling the program may fix this problem."  From where do
>> I get readline4.dll?

> Cygwin's bc does not depend on this library and it would not give you
> this error message either.  I suggest you try "/usr/bin/bc" from a
> Cygwin shell and then think about what you want to have your PATH look
> like.

I wonder which setup program that was, and how your environment is set up?

That message is from a native Windows port of bc, installed under/by 
Mingw/64, Msys/2, Chocolatey or some other native Windows port installer 
that does not handle library dependencies. You would have to install 
that environment's readline library using their setup program.

If you have installed Cygwin, you must start it using (perhaps some 
minor variation of) the provided shortcuts, command files, or scripts, 
and ensure the Cygwin path is set with Cygwin /usr/bin/ near the start, 
possibly preceded by your own local script directory/-ies: e.g.

	$HOME/bin:/usr/local/bin:/usr/bin

-- 
Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada

This email may be disturbing to some readers as it contains
too much technical detail. Reader discretion is advised.
[Data in binary units and prefixes, physical quantities in SI.]