Re: port-vax/41139: pipe(2) seems broken on VAX

[Anders Magnusson <ragge%ludd.ltu.se@localhost>]

The following reply was made to PR port-vax/41139; it has been noted by GNATS.

From: Anders Magnusson <ragge%ludd.ltu.se@localhost>
To: Christos Zoulas <christos%zoulas.com@localhost>
Cc: gnats-bugs%NetBSD.org@localhost, gnats-admin%NetBSD.org@localhost, 
netbsd-bugs%NetBSD.org@localhost,
        tsutsui%ceres.dti.ne.jp@localhost
Subject: Re: port-vax/41139: pipe(2) seems broken on VAX
Date: Wed, 08 Apr 2009 08:01:21 +0200

 Christos Zoulas wrote:
 > |     One other note - this also appears to have been the problem with using 
 > |  scp on the vax to transfer files.  My scp copies no longer get corrupted 
 > |  data.  [Since scp does a pipe to run the remote ssh command and copies 
 > the 
 > |  data from the pipe, this makes sense.]
 > 
 > 
 > Can't we do?
 > 
 >      while (len >= 64K) {
 >              movc3 64K-1, ...
 >              len -= 64K-1;
 >      }
 >      movc3 len, ...
 > 
 > In kcopy, copyin and copyout?
 > 
 It may be worth trying, but it also may require significantly more code.
 The movc3 instruction handles overlapping copies, but if the data block is
 larger than 64k then it must be done manually.  This is only a problem for 
kcopy,
 copy{in,out} should not overlap :-)
 
 The cvs problem is most likely something else, it existed before the fast pipe 
code.
 
 -- Ragge