perldoc is broken in 9, 10 and CURRENT with "xterm" TERM

[Chris H]

On Wed, 15 Apr 2015 17:35:54 +0100 Matthew Seaman <matthew at FreeBSD.org> wrote

> On 2015/04/15 17:26, Lev Serebryakov wrote:
> > 
> >  perldoc from perl 5.16 and perl 5.18 on 9, 10 and CURRENT shows ESC
> > codes like this:
> > 
> > "ESC[4mfieldsESC[24m") that do ESC[1mnot ESC[22minclude
> > 
> >  Terminal tried is "xterm" (PuTTY and cygwin's rxtv) and "cygwin"
> > (cygwin's ssh from console).
> > 
> >  Adding screen or tmux in mix doesn't help, either.
> > 
> >  I've found closed PR, which explains or fixes nothing:
> > 
> >  https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=162463
> 
> As a workaround, add this to your environment:
> 
> PERLDOC_PAGER='less -+C -E -R'
This all seems so kludgy. In fact I ended up creating a port
to remove the ANSI nonsense that shows up in the (type)script
output generated by clang, in an effort to make it more
readable. This stuff all seemed to show up about the time
vt(4) did. Is there a coloration?
ie; loader.conf(5)
kern.vty=vt  # current default
kern.vty=sc  # previous default

Also given that the default .cshrc provides
setenv	PAGER	more

All of the suggested "fixes" just seem wrong, or more
concisely; the proposed "fixes" cure the symptoms, but
not the problem.

What is the *actual* reason (cause)?

Thanks.

--Chris
> 
>     Cheers,
> 
>     Matthew