Bug #70855 for Test-Harness: Very weird bug of `prove' w.r.t. trapped signals and fd redirections in TAP producers

Hello. I've recently encountered a very strange issue with prove 3.17 on Solaris 10 and Debian GNU/Linux (it took me half a day to produce this almost-minimal test case!). Here is the problematic data: $ cat > t <<'END' trap 'exit $?' 0 trap "echo 'caught signal SIGINT' >&9; exit 1" 2 trap "echo 'caught signal SIGPIPE' >&9; exit 1" 13 set -x sleep 5 echo 1..0 END And here is what happens on the two systems... ============= Solaris 10 ============= Some system info: $ uname -rmsv SunOS 5.10 Generic_144489-06 i86pc $ prove --version TAP::Harness v3.17 and Perl v5.12.2 $ bash --version GNU bash, version 3.2.51(1)-release (i386-pc-solaris2.10) Copyright (C) 2007 Free Software Foundation, Inc. How to reproduce the issue: $ prove -e bash ./t 9>&2 # Wait a couple of seconds, then hit Ctrl-C ./t .. + sleep 5 ^Ccaught signal SIGINT caught signal SIGPIPE caught signal SIGPIPE Wait, where are those SIGPIPES coming from? And why there are two of them? And it gets funnier if one uses the system Bourne Shell or Korn Shell instead of Bash: $ prove -e /bin/sh ./t 9>&2 # Wait a couple of seconds, then hit Ctrl-C + sleep 5 ^Ccaught signal SIGINT caught signal SIGPIPE caught signal SIGPIPE ... last line repeated ~ 25000 times ... $ ls -l core # The shell didn't dump core, though. core: No such file or directory $ prove -e /bin/ksh ./t 9>&2 # Wait a couple of seconds, then hit Ctrl-C + sleep 5 ^Ccaught signal SIGINT caught signal SIGPIPE caught signal SIGPIPE ... last line repeated ~ 6000 times ... $ file core # The shell dumped core now! core: ELF 32-bit LSB core file 80386 Version 1, from 'ksh' ================= Debian Unstable ================= Some system info: $ lsb_release -idrc Distributor ID: Debian Description: Debian GNU/Linux testing/unstable Release: testing/unstable Codename: n/a $ uname -rmsv Linux 2.6.30-2-686 #1 SMP Sat Sep 26 01:16:22 UTC 2009 i686 $ bash --version GNU bash, version 4.1.5(1)-release (i486-pc-linux-gnu) Copyright (C) 2009 Free Software Foundation, Inc. $ dpkg -l dash ii dash 0.5.5.1-7.4 POSIX-compliant shell $ dpkg -l ksh ii ksh 93u-1 The real, AT&T version of the Korn shell How to reproduce the issue: $ prove -e bash ./t 9>&2 # Wait a couple of seconds, then hit Ctrl-C ./t .. + sleep 5 ^C caught signal SIGINT caught signal SIGPIPE caught signal SIGPIPE Again those two SIGPIPE; but ksh only gets one: $ prove -e ksh ./t 9>&2 ./t .. + sleep 5 ^C caught signal SIGINT caught signal SIGPIPE It gets funnier if one uses the Alquist shell: $ prove -e /bin/dash ./t 9>&2 # Wait a couple of seconds, then hit Ctrl-C + sleep 5 ^Ccaught signal SIGINT caught signal SIGPIPE caught signal SIGPIPE ... last line repeated ~ 28000 times ... ================= Let me know if you need more information. Regards, and thanks for you great software, Stefano