probable problem with redirections and screen

[Vincent Lefevre <Vincent.Lefevre@ens-lyon.fr>]

I start a perl script, say my_script, with the following command line:

  nice -2 zsh -c "./my_script 2>&1 2> secstep.out"

to redirect the error output to both the terminal and secstep.out.
When I did this in an rxvt, there was no problem. Now, I start the
script from screen, and sometimes the script dies silently. In the
terminal, I only have the normal output (to stdout) of the script
and the following line:

nice -2 zsh -c   942.81s user 10.38s system 2% cpu 10:30:06.84 total

but no error message, and no non-zero exit status (when I type
"nice -2 zsh -c false", "zsh: exit 1     nice -2 zsh -c false"
is displayed; with my script, there's nothing). So, I don't think
this comes from Perl. Perhaps zsh (the one that starts my_script)
dies before my_script?

The file secstep.out is generally empty. I think the problem occurs
when the script wants to write something to stderr (but sometimes,
writing to stderr doesn't kill the process).

Is there anything I shouldn't do concerning MULTIOS redirections
when I use screen? Or is there a bug in zsh (I use zsh 3.1.5)?

TIA for any information,

-- 
Vincent Lefevre <Vincent.Lefevre@ens-lyon.fr> - PhD stud. in Computer Science
Web: <http://www.vinc17.org/> or <http://www.ens-lyon.fr/~vlefevre/> - 100%
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