[racket] ffi-lib: couldn't open "libreadline.dll.5" - Windows XP

From: Matthew Flatt (mflatt at cs.utah.edu)
Date: Sat Jan 1 10:30:47 EST 2011

At Sat, 1 Jan 2011 07:20:48 -0800 (PST), Chris Nelson wrote:
> I'm a new user of Racket just working through the introduction examples and 
> such. I've finished "Quick: An Introduction to Racket with Pictures" with 
> DrRacket and I'm attempting to complete More: "Systems Programming with Racket" 
> through cmd.exe.  However I'm receiving the following message after loading 
> Racket at the command line. 
> --------------
> Welcome to Racket v5.0.2.
> ffi-lib: couldn't open "libreadline.dll.5" (The specified module could not be 
> found.; errno=126)
> --------------
> Readline does appear to be installed in my racketrc.rktl, and DrRacket aggrees 
> so maybe racket.exe is looking in a different path than DrRacket in Windows.

Readline isn't useful when using "cmd.exe" in Windows, because the
Windows command shell gives you readline-like functionality
automatically. There's a note to that effect before the
`install-readline!' example in "More", but maybe it needs to be more
clear that readline typically isn't available at all under Windows.

So, I think you want to just remove the `readline' loading from your

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