use Test::Simple tests => 3;
ok !open(my $fh, '|-', 'nonexistent program'), 'string form of open fails';
ok open(my $prince, '|-', 'nonexistent program 2>/dev/null'), 'but succeeds if shell uses redirection';
ok !open(my $none, '|-', 'nonexistent', 'program'), 'list form of open fails, as it should';
__END__
1..3
ok 1 - string form of open fails
ok 2 - but succeeds if shell uses redirection
ok 3 - list form of open fails, as it should

##</code><code>##

$ strace -f -e clone,execve perl -e'open(my $fh, "|-", "nonexistent program")'
execve("/usr/bin/perl", ["perl", "-eopen(my $fh, \"|-\", \"nonexisten"...], [/* 45 vars */]) = 0
clone(child_stack=0, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, child_tidptr=0xb74f7a68) = 7792
Process 7792 attached
[pid  7792] execve("/home/aitap/perl5/bin/nonexistent", ["nonexistent", "program"], [/* 45 vars */]) = -1 ENOENT (No such file or directory)
[pid  7792] execve("/home/aitap/scripts/nonexistent", ["nonexistent", "program"], [/* 45 vars */]) = -1 ENOENT (No such file or directory)
[pid  7792] execve("/home/aitap/bin/nonexistent", ["nonexistent", "program"], [/* 45 vars */]) = -1 ENOENT (No such file or directory)
[pid  7792] execve("/usr/local/bin/nonexistent", ["nonexistent", "program"], [/* 45 vars */]) = -1 ENOENT (No such file or directory)
[pid  7792] execve("/usr/bin/nonexistent", ["nonexistent", "program"], [/* 45 vars */]) = -1 ENOENT (No such file or directory)
[pid  7792] execve("/bin/nonexistent", ["nonexistent", "program"], [/* 45 vars */]) = -1 ENOENT (No such file or directory)
[pid  7792] execve("/usr/local/games/nonexistent", ["nonexistent", "program"], [/* 45 vars */]) = -1 ENOENT (No such file or directory)
[pid  7792] execve("/usr/games/nonexistent", ["nonexistent", "program"], [/* 45 vars */]) = -1 ENOENT (No such file or directory)
[pid  7792] +++ exited with 1 +++
--- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=7792, si_uid=1000, si_status=1, si_utime=0, si_stime=0} ---
+++ exited with 0 +++

##</code><code>##

$ strace -f -e clone,execve perl -e'open(my $fh, "|-", "nonexistent program 2>/dev/null")'
execve("/usr/bin/perl", ["perl", "-eopen(my $fh, \"|-\", \"nonexisten"...], [/* 45 vars */]) = 0
clone(Process 7809 attached
child_stack=0, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, child_tidptr=0xb753ea68) = 7809
[pid  7809] execve("/bin/sh", ["sh", "-c", "nonexistent program 2>/dev/null"], [/* 45 vars */]) = 0
[pid  7809] +++ exited with 127 +++
--- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=7809, si_uid=1000, si_status=127, si_utime=0, si_stime=0} ---
+++ exited with 0 +++