Re: lost output from asynchronous lists

[Ralf Wildenhues]

* Stephane Chazelas wrote on Sun, Nov 02, 2008 at 09:53:15AM CET:
> On Sat, Nov 01, 2008 at 11:21:01PM -0000, Sven Mascheck wrote:
> [...]
> > >>>>  : > stdout > stderr
> [...]
> > > It fails on old Ultrix sh, which can't redirect the same fd more than once
> > > in a single statement.  But that platform is relatively dead these days.
> > 
> > More detailed:
> > 
> > - It actually works (also on Ultrix) but it is not robust
> >    in any traditional Bourne shell (except where fixed by the vendor):
> > 
> >   $ echo x y > file1    > file2 # ok, all output in file2
> >   $ echo x   > file1 y  > file2 # not ok, all output in file1 instead of 
> > file2

IIRC then the Ultrix shell also output an undesirable warning,
but I don't know whether that was in conjunction with eval only.
Quoting autoconf.info:

|    When catering to old systems, don't redirect the same file descriptor
| several times, as you are doomed to failure under Ultrix.
| 
|      ULTRIX V4.4 (Rev. 69) System #31: Thu Aug 10 19:42:23 GMT 1995
|      UWS V4.4 (Rev. 11)
|      $ eval 'echo matter >fullness' >void
|      illegal io
|      $ eval '(echo matter >fullness)' >void
|      illegal io
|      $ (eval '(echo matter >fullness)') >void
|      Ambiguous output redirect.

Cheers,
Ralf