bug#2588: 23.0.90; Man buffer improperly formatted - wrong width

[Eli Zaretskii]

> From: "Drew Adams" <drew.adams@oracle.com>
> Date: Fri, 6 Mar 2009 12:51:59 -0800
> Cc: 
> 
> M-x set-variable RET pop-up-frames RET t
>  
> Resize the current frame so that it is, say, only 30 chars wide.
>  
> M-x man RET bash RET
>  
> Buffer *Man bash* is shown in a new frame. The frame has the usual
> default width of 80 chars.  But the text of the buffer is formatted to
> be only 30 chars wide.

I cannot reproduce this on my system, but I think I know why, see
below.

> This same bug exists for Emacs 22 (e.g. 22.3) and Emacs 21
> (e.g. 21.3.1).  Emacs 20 (e.g. 20.7) has no such bug.  

That's because Emacs 20 didn't set COLUMNS in the environment before
invoking the `man' program.  But that had other adverse effects on X,
see the comments in man.el where it sets COLUMNS.

> In Emacs 21, the bug occurs even without loading the two Cywin helper
> libraries.  With my SHELL var set to /bin/bash.exe, I cannot test
> Emacs 22 or 23 without loading those libraries, but I suspect the same
> bug occurs, as it does in Emacs 21.  IOW, I don't think this has
> anything to do with using Cygwin.

Actually, it does have something to do with Cygwin: I'm guessing your
man.exe comes from Cygwin, and tries to honor the COLUMNS environment
variable.  My man.exe is a natively compiled clone of the Unix `man'
command, and it doesn't pay attention to COLUMNS, so it always
produces text whose width assumes an 80-column display, no matter what
COLUMNS says.